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Introduction

♠ ♥ ♦ ♣

This book is a collection of my bidding systems. I have been studying forcing club systems since reading Good, Better, Best by Jan Eric Larsson, whose simulations show that forcing club systems tend to outperform other systems. I believe opening 1♣ for all strong hands is a superior treatment.

Strawberry Polish Club is a BTU-flavored Polish Club largely based on Polish Club 2020: Expert. Polish Club serves as a gateway to the world of forcing clubs. It is 5-card major. Its main opening range is 12–17. Sharing these properties, it has similar bidding structure to 2/1, the lingua franca of modern bridge.

Blueberry Cottontail Club is a modernized mix of Blue Club and Cottontail Club along with new ideas from BTU. It is a 4-card major strong club system with a moderately strong notrump. It is highly experimental and subject to change without notice.

Hand evaluation

  • HCP: the well-known Milton Work’s 4321 count
  • Total points: HCP + distribution points (void = 3, singleton = 2, doubleton = 1, subtract 1 for each short suit with HCP)
  • Zar: 6-4-2-1 + Zar distribution points (a + b + a - d, where the letters are the number of cards from the longest to the shortest suit)
  • Fifths: 4.0–2.8–1.8–1.0–0.4, adjusted HCP for notrump contracts especially 3NT
  • BUM-RAP: 4.5–3–1.5–0.75–0.25, adjusted HCP for suit contracts
  • NLTC: Count 1.5–1.0–0.5 losers for each missing AKQ

NLTC is a good single hand evaluator but not very additive. It suits preemptive initial actions but not for showing supports. I wrote a blog article on that topic.

Stopper

I evaluate stopper quality as GIB does.

  • Partial stop: length + HCP = 4
  • Likely stop: length + HCP = 5
  • Stop: A, QJx, or length + HCP at least 7
  • Two stops: length + HCP at least 8

Punctuations

Descriptions in bidding tables are dense in information. To make them concise, I use abbreviations suggested by WBF. Besides, for natural reading flow, I use usual punctuation marks to connect conditions. Their meanings are usually self-explanatory in a bidding table.

  • The comma (,) works as AND.
  • The period (.) works as OR.
  • The colon (:) follows general description of the call.

A notable example is the 1♣ opening in Strawberry Polish Club.

References

General methods

Polish Club

Precision Club

Other strong clubs

Legacy system notes

I used to collate my system notes in BML. It is a powerful tool for typesetting multi-layered bidding structures. However, I also yearn interconnectivity in Markdown. Markdown has hyperlinks. I can break down my systems into reusable chapters and then link them together.

The below are my legacy system notes built with BML. I keep them here for now because I have not yet fully covered them in this book. I will eventually remove them when the migration is complete.

Strawberry Polish Club

Our Polish Club opening contains minimum clubs like Polish Club 2020: Expert. I adjust the 1♦ opening to contain 18–20 unbalanced diamonds with no 4-card major. This method makes 1♣-1♦-3m limited enough (21–23) for their level.

-
1♣!F, Polish Club:
12–14, 2–4♠, 2–4♥, 2–4♦, 2–4♣.
12–17, 5+♣ or 4414.
18+, not suitable for 1♦.
1♦
12–17, 5+♦ or 4♦(441).
18–20, UNBAL, 5+♦, 0–3♠, 0–3♥.
1♥12–17, 5+♥
1♠12–17, 5+♠
1NT15–17, 2–4♠, 2–4♥, 2–6♦, 2–6♣
2♣!PRE, 4+♠, 4+♥, not 44(32) if VUL
2♦!PRE, 6+M
2M!PRE, 5=#, 4+m
2NT!UNT, 5+♦, 5+♣
3XPRE, 7+#
3NT!Gambling, SOL 7+m, 0–1 outside A/K
4♣!PRE, S-SOL 8+M, 0–1 outside A/K
4♦!PRE, SOL 8+M, no outside A/K
4MPRE, 8+#
4NT!UNT, 6+♦, 6+♣

The notrump ladder

  • 12–14: 1♣-1♦-1M
  • 15–17: 1NT
  • 18–20: 1♣-1♦-1NT
  • 21–23: 1♣-1♦-2♦
  • 24+: 1♣-1♦-2NT

Polish 1♣

This Polish Club has 3 variants:

  • 12–14, 2–4♠, 2–4♥, 2–4♦, 2–4♣
  • 12–17, 5+♣ or 4414
  • 18+, not suitable for 1♦

Note that 2♣ is no longer natural since Polish Club 2020: Expert. 1♣ takes care of all ♣-suited hands.

I move invitational hands out of 1♣-1♦ relay to make it non-forcing. I believe this method is more resilient to interference.

1♣-Quasi-NAT or 18+
1♦!NF ART NEG, 0–9
1♥F, 7+, 4+♥
1♠F, 7+, 4+♠
1NTBAL CONST, 8–10, 2–3♠, 2–3♥, 2–5♦, 2–5♣
2♣FG, 5+♣
2♦FG, 5+♦
2♥!P/C, 7–9, 4+♥, 5+♠
2♠!INV, 10–11, 0–3♠, 0–3♥, 2–5♦, 2–5♣
2NT!FG, 2–3♠, 2–3♥, 3–4♦, 3–4♣
3♣INV, 9–11, 6+♣
3♦INV, 9–11, 6+♦
3MPRE, 3–6, 7+#
3NT12–15, 33(43)
4♣!PRE, S-SOL 8+M, 0–1 outside A/K
4♦!PRE, SOL 8+M, no outside A/K
4MPRE, 8+#

1♣-3♣♦ and 1♣-3M look unrelated, yet they serve the same purpose: move the best single suiters out of 1♣-1♦.

P-1♣

Game-forcing responses simplify to corresponding invitations.

P-1♣-Quasi-NAT or 18+
2♣INV, 5+♣, 0–3♠, 0–3♥
2♦INV, 5+♦, 0–3♠, 0–3♥
2♠!UNBAL INV, 0–3♠, 0–3♥, 4–5♦, 4–5♣
2NTBAL INV, 2–3♠, 2–3♥, 2–5♦, 2–5♣

Negative 1♦

In our version of Polish Club, the 1♦ relay denies invitational values. This relay contains weak hands without another suitable bid.

StrengthDistribution
0–6Any
7–90–3♠, 0–3♥

We swap the 2♦ and 2NT responses for better constructiveness by courtesy of Ting-Yu Ye (TpKotoba).

1♣-1♦-0–9
PBAL MIN, 4=♦
1♥F, 12–19, 4+♥ or BAL MIN 3=♥
1♠F, 12–19, 4+♠
1NTBAL, 18–20, 2–4♠, 2–4♥, 2–6♦, 2–6♣
2♣NF, 12–20, UNBAL 5+♣
2♦!NF, 21–23, 1–4♠, 1–4♥, 0–5♦, 0–5♣
2♥FG, 20–23, 5+♥
2♠FG, 20–23, 5+♠
2NTFG, 24+
3♣FG, 21–23, 6+♣
3♦FG, 21–23, 6+♦
3♥!SPL, 21–23, 40(54)
3♠!SPL, 21–23, 04(54)
3NT!Gambling, SOL 7+♣, likely stops in two side suits

1♣-1♦-1M

Given that Polish Club is a 5-card major system, the major suit left in 1♣-1♦-1M gets longer when stronger.

StrengthLength
12–144=# or occasional UNBAL 3=#
15–174=# or occasional 5+# 6+♣
18–195+# or UNBAL 4=#

I reuse 2NT for the most pesky hands in the range of 1♣-1♦.

1♣-1♦-1M-12–19, usually 4+M
1NTBAL, 5–7, 1–3M
2MNF, 4–6, 4–5# or UNBAL 3=#
2NT!UNT, 7–9, usually 5+♦ 5+♣
3♣MAX, 7–9, 6+♣
3♦MAX, 7–9, 6+♦
3MNF, 4–6, 5+#
1♣-1♦-1♥-12–19, usually 4+♥
1♠NF, 4–6, 4+♠
2♠NF, 4–6, 6+♠
1♣-1♦-1♠-12–19, usually 4+♠
2♥NF, 4–6, 5+♥

1♣-1♦-1NT

1♣-1♦-1NT-BAL 18–20
2♣!STAY, Garbage STAY, or INV 5=♠
2♦!TRF, 5+♥
2♥!TRF, 5+♠
2♠!Minor suit Multi/STAY, 6+m or FG 4+♦ 4+♣
2♠-2NT1–3♦, 1–3♣
2♠-3♣!4+♦
2♠-3♦!4+♣
2NTNAT INV
3♣INV, 6+♣
3♦INV, 6+♦
3♥!INV, 5+♠, 5+♥
3♠!Choice of games, 5+♠, 5+♥
4♣!Gerber BW
4♦!Texas TRF, 6+♥
4♥!Texas TRF, 6+♠

1♣-1♦-2♣

The 2♣ rebid is wide, but worry not. Lebensohl fits in this reverse-like auction.

1♣-1♦-2♣-12–20, UNBAL 5+♣
2♦NF, 5–9, 6+♦
2♥NF, 4–6, 5+♥
2♠NF, 4–6, 5+♠
2NT!LEB, 5–7, 3+♣ or 7+♦
3♣NF, 7–9, 4+♣
3♦NF, 7–9, 7+♦

1♣-1♦-2♦

The 2♦ rebid shows a nearly balanced hand with 21–23 HCP. If you can force to game, bid as if partner opened a natural 2NT. Otherwise, try to sign off at the 2-level.

1♣-1♦-2♦-21–23, 1–4♠, 1–4♥
PTo play, usually 5+♦
2♥NF, 4+♥
2♠NF, 4+♠
2NTS/O
3♣!FG, STAY
3♦!TRF, 5+♥
3♥!TRF, 5+♠
3♠!Minor suit Multi/STAY, 6+m or FG 4+♦ 4+♣
3NTS/O

1♣-1♦-2NT

Opener forces to game single-handedly by rebidding 2NT. The shape of such a strong hand is predominantly balanced. I would treat it as a strong notrump that allows 5-card major.

1♣-1♦-2NT-24+
3♣!Muppet STAY, 3+M
3♦!Muppet TRF, 5+♥
3♥!TRF, 5+♠
3NTS/O
4♣!Gerber BW
4♦!Choice of games, 5+♠, 5+♥
4♥!!SPL, 0–1♥, 2–3♠, 4–5♦, 4–5♣
4♠!!SPL, 0–1♠, 2–3♥, 4–5♦, 4–5♣
4NTQUANT INV to 6NT

Muppet Stayman is an ambitious convention that tries to find both 5-3 and 4-4 major fits. It swaps 3♥ and 3NT steps from Puppet Stayman to find 3-5 spades. Note that responder rebids 3♠ to deny spades. This gadget, similar to Smolen, lets opener declare.

1♣-1♦; 2NT-3♣-Muppet STAY
3♦!(R), 4=M
3♥!NEG, 0–3♠, 0–3♥
3♥-3♠!(R), 0–4♠
3♥-3NT!TRF, 5+♠
3♠5+♠
3NT!TRF, 5+♥

Muppet Stayman also affects transfer to hearts to find 4-4 spade fit. Again, responder rebids 3♠ to deny spades.

Opener can reject the transfer with 3NT. Such entitlement is why I choose Muppet over Romex. Romex Stayman allows a garbage variant, but it is not very useful here because the auction is already game-forcing.

1♣-1♦; 2NT-3♦-Muppet TRF
3♥2+♥
3♥-3♠!(R), 0–3♠
3♥-3NT!TRF, 4+♠
3♠5+♠
3NT0–1♥, 0–4♠

Positive 1M

The positive responses 1♣-1♥♠ show 7+ points and 4+ cards. They are as natural as in a natural bidding system. We also use conventions from 2/1, a ubiquitous 5-card major system.

Odwrotka 1♣-1M-2♦ is a fit reverse showing a game-forcing 3+ card support. The jump reverse of the other major shows a game-forcing minor two suiter to alleviate the burden on 2NT.

1♣-1♥-7+, 4+♥
1♠F, 4+♠
1NTBAL 12–14, 2–3♠, 2–3♥
2♣UNBAL, 12–17, 5+♣, 0–3♠, 0–3♥
2♦!FG, 3+♥
2♥MIN, 12–14, 4=♥
2♠!FG, 5+♦, 5+♣
2NTFG, 2–3♠, 1–2♥, 3–5♦, 3–5♣
3♣FG, 6+♣
3♦FG, 6+♦
3♥INV, 15–17, 4+♥
3♠!SPL, 0–1♠, 4+♥
3NTSOL 7+♣, partial stops in ♠ and ♦
4♣!SPL, 0–1♣, 4+♥
4♦!SPL, 0–1♦, 4+♥
1♣-1♠-7+, 4+♠
1NTBAL 12–14, 2–3♠, 2–3♥
2♣UNBAL, 12–17, 5+♣, 0–3♠, 0–3♥
2♦!FG, 3+♠
2♥FG, 5+♥
2♠!MIN, 12–14, 4=♠
2NTFG, 0–2♠, 2–4♥, 2–5♦, 2–5♣
3♣FG, 6+♣
3♦FG, 6+♦
3♥!FG, 5+♦, 5+♣
3♠INV, 15–17, 4+♠
3NTSOL 7+♣, partial stops in ♥ and ♦
4♣!SPL, 0–1♣, 4+♠
4♦!SPL, 0–1♦, 4+♠
4♥!SPL, 0–1♥, 4+♠

BTU 3-way checkback

We use BTU-style 3-way checkback to an XYZ auction. There are 3 artificial relays in the 3-way checkback:

  • 2♣: several variants:
    • to play 2X
    • strongly shaped invitation
    • balanced invitation or choice of games
  • 2♦: game-forcing checkback, usually a choice of games
  • 2NT: transfer to clubs

As a corollary, natural 2X are wide-range invitations and 3X become slam tries.

1♣-1♥-1♠

In this particular case of BTU checkback, opener can pass 1♣-1♥; 1♠-2♣ with minimum long clubs. Otherwise, BTU checkback is forcing.

1♣-1♥-1♠-F, 4+♠
1NTMIN, 7–10, 0–3♠, 4–5♥
2♣!BTU CB, NF
2♦!FG CB
2♥INV, 5+♥
2♠INV, 4+♠
2NTTRF, PRE or FG, 6+♣
3♣S/T, 5+♣, 5+♥
3♦S/T, 5+♦, 5+♥
3♥S/T, 6+♥
3♠S/T, 4+♠
3NT12–15, 0–3♠, 4=♥, 0–5♦, 0–5♣
1♣-1♥; 1♠-1NT-NAT MIN
2♣NF, 12–15, 5+♣
2♦!4SF1, INV+, 0–2♥
2♥INV, 3=♥
2♠FG, 5+♠
2NTINV, 16–17, 0–2♥
3♣FG, 6+♣
3♦FG, 6+♦
3♥FG, 5+♠, 3=♥
1♣-1♥; 1♠-2♣-BTU CB
PS/O, 12–13, 6+♣
2♦!MIN, 12–15
2♥INV, 3=♥
2♠FG, 5+♠, 0–2♥
2NTFG, 4=♠
3♣INV, 16–17, 5+♣, 0–2♥
3♦FG, 5+♦
3♥FG, 5+♠, 3=♥
3♠!FG, 5+♣, 4=♠, 0–2♥
3NTMild S/T, 21–23, 4=♠
1♣-1♥; 1♠-2♣; 2♦-MIN, 12–15
PMIN, 5+♦
2♥UNBAL MIN, 5+♥
2♠MIN, 4+♠
2NTBAL INV
3♣INV, 6+♣
3♦INV, 6+♦
3♥INV, S-SOL 6+♥
3♠INV, 4+♠, 5+♥

1♣-1♥-1NT

1♣-1♥-1NT-BAL 12–14
2♣!BTU CB, F1
2♣-2♦!P/C
2♣-2♥MAX, 3=♥
2♦!FG CB
2♥INV, 5+♥
2♠INV, 4+♠
2NTTRF, PRE or FG, 6+♣
3♣S/T, 5+♣, 5+♥
3♦S/T, 5+♦, 5+♥
3♥S/T, 6+♥
3♠!SPL, 0–1♠, 6+♥
3N12–15, 4=♥
4♣!SPL, 0–1♣, 6+♥
4♦!SPL, 0–1♦, 6+♥
1♣-1♥; 1NT-2♣; 2♦-BAL 12–14, P/C
2♥S/O, 5+♥
2♠INV, 4+♠, 6+♥
2NTBAL INV
3♣INV, 6+♣
3♦INV, 6+♦
3♥INV, S-SOL 6+♥
3NTChoice of games, 5♥(332)

1♣-1♠-1NT

1♣-1♠-1NT-BAL 12–14
2♣!BTU CB, F1
2♣-2♦!P/C
2♣-2♥MAX, 4=♥
2♣-2♠MAX, 3=♠
2♦!FG CB
2♥INV, 4+♥, 5+♠
2♠INV, 5+♠
2NTTRF, PRE or FG, 6+♣
3♣S/T, 5+♣, 5+♠
3♦S/T, 5+♦, 5+♠
3♥S/T, 5+♥, 5+♠
3♠S/T, 6+♠
3NT12–15, 4=♠
4♣!SPL, 0–1♣, 6+♠
4♦!SPL, 0–1♦, 6+♠
4♥!SPL, 0–1♥, 6+♠
1♣-1♠; 1NT-2♣; 2♦-BAL 12–14, P/C
2♥INV, 5+♥, 5+♠
2♠S/O, 5+♠
2NTBAL INV
3♣INV, 6+♣
3♦INV, 6+♦
3♥INV, 4+♥, 6+♠
3♠INV, S-SOL 6+♠
3NTChoice of games, 5♠(332)

Odwrotka with the strong 2♥ relay

We use the relay structure in Polish Club 2020: Expert. The 2♥ response to Odwrotka is a slam try with 11+ HCP or a certain fit and <= 8.0 NLTC. The relay structure generally lets the strong opener declare notrump.

1♣-1M-2♦-FG, 3+M
2♥!S/T (R), 11+
2♥-2♠!(R)
2♥-2NTProbably (4333)
2♠!NEG, 7–10, 4=M
2♠-2NT!Ask for a side suit, a 5-card minor or the other 4-card major
2NT!MIN, 7–10, 5=M, not BAL
2NT-3♣!Ask for the side suit
3♣Mild S/T, 9–11, 5+♣, 4=M
3♦Mild S/T, 9–11, 5+♦, 4=M
3M!MIN, 7–10, BAL 5=M
3oM!SPL, 7–10, 0–1#, 6+M
3NTMIN, 7–10, 6+M
4♣!SPL, 7–10, 0–1♣, 6+M
4♦!SPL, 7–10, 0–1♦, 6+M

Relay systems can be cryptic! I am summing up why we arrange the steps in this way.

  • 2♥: The lowest step layers strong hands. We can repeat the whole structure inside. This step follows the logic of (reverse) Lebensohl.
  • 2♠: The second step holds the possibility of a misfit, 4 cards. We need space to explore games in the other strains.
  • 2NT: Unbalanced fit! Opener never settles in 3NT. Feel free to bid notrump.
  • 3M: Balanced fit! Give opener a chance to declare 3NT with a flat hand.
  • 3m: Take some hands out of the nebulous 2♠. These hands suggests a minor suit slam.
  • Others: These Splinter-level steps are made for big fits.
1♣-1M; 2♦-2♥; 2♠-(R)
2NT4=M
2NT-3♣!Ask for a side suit
3♣4+♣, 5=M
3♦4+♦, 5=M
3oM4+#, 5=M
3M!BAL 5=M
3NT!6+M
4♣!SPL, 0–1♣, 6+M
4♦!SPL, 0–1♦, 6+M
1♣-1M; 2♦-2♥; 2♠-2NT; 3♣-Ask for a side suit
3X4+#
3M!4+♣
3NT4M(333)

Positive 1NT, 2♠, and 2NT

I group these suitless positive responses together for simplicity. These responses deny 4-card majors and 6-card minors. I also list 1♣-3NT here as reference because it takes precedence over 1♣-2NT.

1♣-StrengthDistribution
1NT8–102–3♠, 2–3♥, 2–5♦, 2–5♣
2♠!10–110–3♠, 0–3♥, 2–5♦, 2–5♣
2NT12+2–3♠, 2–3♥, 3–4♦, 3–4♣
3NT12–1533(43)

1♣-1NT

I took the artificial 2♦ relay from FunBridge. I found it better than most Polish Club literature.

1♣-1NT-BAL 8–10
2♣S/O, 12–14, 6+♣
2♦!INV+ (R)
2MS/T, 18+, 5+#
2NTINV, 14–15
3♣S/T, 18+, 6+♣
3♦S/T, 18+, 6+♦
3MS/T, 18+, 7+#
3NTS/O, 16+
4♣♦S/T, SOL 7+#
1♣-1NT-2♦-INV+ (R)
2♥!5–6♣
2♠!5–6♦
2NTMIN, 2–4♦, 2–4♣
3♣!MAX, 2245
3♦!MAX, 2254
3♥!MAX, 6=♣
3♠!MAX, 6=♦
3NTMAX, 2–4♦, 2–4♣

1♣-2♠!

I move unbalanced invitations here from 1♣-1♦. Opener declares notrump anyway, so 1♣-2♠ need not be balanced.

1♣-2♠-INV 10–11
2NTS/O, 12–13
3♣S/O, 12–13, 6+♣
3♦!S/T, 18+, 0–4♠, 0–4♥
3MS/T, 18+, 5+#
3NTS/O
4♣♦♥♠S/T, SOL 7+#

P-1♣-2♠ only contains unbalanced hands of both minors. Hence, 3♦ becomes a reasonable signoff.

P-1♣-2♠-INV, 4–5♦, 4–5♣
3♦S/O, 12–13, 4+♦

1♣-2NT

Moving balanced game force from 3NT to 2NT was a brilliant idea from Polish Club 2005. It is difficult to search for a major suit slam after 1♣-3NT. Therefore, 1♣-3NT is restricted to a flat minimum game force.

I make 1♣-2NT-3NT highly descriptive here to help slam exploration. This method makes 3♣♦ inclusive like relays.

1♣-2NT-BAL FG
3♣5+♣
3♦!0–4♣
3MS/T, 5+#
3NTS/T, 15–17, 4414
4♣♦♥♠S/T, SOL 7+#

P-1♣-2NT simplifies to a balanced invitation, which is in turn similar to unpassed 1♣-2♠. I import continuations from 1♣-2♠ as a natural consequence.

P-1♣-2NT-BAL INV
3♣S/O, 12–13, 6+♣
3♦!S/T, 18+, 0–4♠, 0–4♥
3MS/T, 18+, 5+#
3NTS/O
4♣♦♥♠S/T, SOL 7+#

Game-forcing 2♣♦

The positive responses 2♣♦ show a longest suit with 5+ cards. They are game-forcing by unpassed hand like 2/1. This method helps finding minor suit slams. I spell out the minor suits because there is a subtle difference between them. Finding a big fit in clubs is easier because opener can have minimum long clubs.

Opener reverses with extra values to utilize higher steps to send information. This avoids an awkward situation Bridge World calls “two temporizers and zero describers.” Deviating from Polish Club 2020: Expert, I define 1♣-2♣♦-2♦♥♠ as reverses. This bidding structure separates 15–17 from 12–14 with a 4-card major. I believe this treatment helps finding the best contract. When we only have a game, we want to play in a major suit despite of a better minor fit. However, we play the best fit in a slam to maximize our chances, especially at IMPs.

1♣-2♣-FG, 5+♣
2♦!S/T (R), 15+, 4+♣
2♥S/T, 15+, 4+♥
2♠S/T, 15+, 4+♠
2NTNearly BAL, 12–14 or 18+
3♣NAT, 12–14 or 18+, 4+♣
3♦S/T, 18+, 6+♦
3♥S/T, 18+, 6+♥
3♠S/T, 18+, 6+♠
3NTNAT, 12–14, 3343
1♣-2♦-FG, 5+♦
2♥S/T, 15+, 4+♥
2♠S/T, 15+, 4+♠
2NTNearly BAL, 12–14 or 18+
3♣NAT, 12–14 or 18+, 5+♣
3♦S/T, 15+, 4+♦
3♥S/T, 18+, 6+♥
3♠S/T, 18+, 6+♠
3NT!S/T, 15–17, 5+♣

I make 1♣-2♦-3NT so because otherwise it would be hard to show these hands. Grouping 12–14 and 18+ together is usually OK because 18+ can explore slams unilaterally.

By passed hand

P-1♣-2♣♦ reduce to natural invitations without a 4-card major. Opener hides 4-card majors in this case.

There is still an important difference between 2♣ and 2♦. Opener can always sign off by passing 2♣ due to a sure 7-card club fit. This is not the case for 2♦.

P-1♣-2♣-INV, 5+♣
2♦S/T, 4+♦
2♥S/T, 5+♥
2♠S/T, 5+♠
2NTBAL S/T
3♣S/T, 4+♣
3♦S/T, 6+♦
3♥S/T, 7+♥
3♠S/T, 7+♠
P-1♣-2♦-INV, 5+♦
2♥S/T, 5+♥
2♠S/T, 5+♠
2NTTo play
3♣To play, 6+♣
3♦S/T, 3+♦
3♥S/T SPL, 0–1♥, 5+♣
3♠S/T SPL, 0–1♠, 5+♣
3NTTo play
4♣S/T, S-SOL 6+♣
4♦S/T, UNBAL 4+♦
4♥S/T, SOL 7+♥
4♠S/T, SOL 7+♠
4NTQUANT INV to 6NT

Reverse Flannery 2♥

Reverse Flannery 1♣-2♥ shows constructive 4+♥, 5+♠. This agreement makes all 4+♥ variants in 1♣-1♠ INV+ and benefits checkback thereafter.

1♣-2♥-CONST, 4+♥, 5+♠
P, 2♠S/O
2NT!LEB
3♣!FG, 2+♠
3♦!FG, 3+♥
3♥INV, 4+♥
3♠INV, 3+♠
3NTS/O

Opener’s rebids resemble BTU Ekren, but the rebids are more forcing because

  • Minimum hands do not contain a 5-card major.
  • Invitational hands are unbalanced.
1♣-2♥-2NT-LEB
3♣!(R)
3♦!3–4♣, 0–1♦, 54(xx)
3♥5+♥
3♠6+♠
1♣-2♥-3♣-FG, 2+♠
3♦!54(xx), at most partial stop in ♦
3♥5+♥
3♠6+♠
3NT54(xx), likely stop in ♦
1♣-2♥-3♦-FG, 3+♥
3♥!54(xx), at most partial stop in ♦
3♠6+♠
3NT54(xx), likely stop in ♦

Competing at the 1-level

The design of the responses already bears competitive bidding in mind. We somehow ignore the meaning of overcalls to deal with artificial and psychic bids. We reorder major suit bids with Transfer Walsh to get a “support double” by accepting the transfer.

We treat 1♣ as a weak notrump more than a club opening. Club support is not very effective. We have a transfer scheme for all levels below 3NT.

  • 1♦♥♠: Transfer to the next strain. The low-level cuebid of 1♠ lets opener declare notrump.
  • From 2Q to 3♥: A weak or strong transfer of 6+ cards.
  • 3♠: Transfer Gambling 3NT.

Natural 1NT is not very useful after a double. Rebrand it as transfer.

1♣-(X)--
XXNF BAL G/T, 10+
1♦!TRF, 7+, 4+♥
1♥!TRF, 7+, 4+♠
1♠!TRF, 7+, 5+♣
1NT!TRF, 7+, 5+♦
2♣♦♥♠PRE, 0–7, 6+#
2NT!TRF, PRE 7+♣ or FG 6+♣
3♣!TRF, PRE 7+♦ or FG 6+♦
3♦!TRF, PRE 7+♥ or FG 6+♥
3♥!TRF, PRE 7+♠ or FG 6+♠
3♠!Gambling, SOL 7+ suit with no stopper outside
3NT!Gambling, SOL 7+ suit with one stopper outside

When RHO bids a suit, natural notrump from Polish Club 2005 right-sides the contract.

1♣-(1Y)--
X!TRF, 7+, 4+ next suit
1♥!TRF, 7+, 4+♠
1♠!TRF to 1NT, 7+
1NTBAL INV, 9–11, 2–3♠, 2–3♥, 2–5♦, 2–5♣
2XINV+, 10+, 5+#
2YZ!TRF, PRE or INV+, 6+ next suit
2♠!TRF, PRE 7+♣ or FG 6+♣
2NTFG with stopper
3♣!TRF, PRE 7+♦ or FG 6+♦
3♦!TRF, PRE 7+♥ or FG 6+♥
3♥!TRF, PRE 7+♠ or FG 6+♠
3♠!Gambling, SOL 7+ suit without stopper
3NT!Gambling, SOL 7+ suit with stopper

Of course 1♣-(1♠)-X is a negative double. Therefore, 2♥ becomes negative free bid. This modern adjunct finds more marginal 4♥ and puts pressure on the opponents by threatening to play 2♥. Moreover, we lose 1♠ that asks for stopper. The direct cuebid 2♠ has to take care of that.

1♣-(1♠)--
X!TRF, 7+, 4+♥
2♥NF, 7–11, 5+♥
2♠!TRF, PRE 7+♣ or FG, ask for stopper

Responder passes

Responder is strictly limited, and 1♣ is prone to psychic bids. Therefore, there are some quirks about cuebids:

  • Responder’s cuebid (not to a X) is natural.
  • Opener’s cuebid after X is natural.
  • Opener’s 2NT is unusual because X includes 21+ “penalty”.
1♣-(1Y)-P--
P12–17
X!12–20, T/O. 21+, PEN
1Z15–20, 4+#
1NT18–20, usually likely stop
2♣12–20, 5+♣
2X20–23, usually 5+#
2Y!21+, ask for stopper
2Z20–23, 5+#
2NT!UNT, 18+, 5+ 5+ two lowest non-adverse suits
3♣, 3X21–23, 6+#
3Y!Gambling, SOL 7+♣, ask for stopper
3Z21–23, 7+#
3NTGambling, SOL 7+♣ with stopper

Transfer Walsh

Transfer to major suits has the same meaning as major suit responses to 1♣. Opener usually bids as if responder had bid the suit naturally. However, opener has a new option: accept the transfer at 1M. This option steals the support double when advancer passes.

Here I only list support rebids for brevity. The complete set of responses is at 1♣-1M.

1♣-(1♦)-X-7+, 4+♥
1♥SUPP, 12–17, 3=♥
2♦!FG, 3+♥
2♥MIN, 12–14, 4=♥
3♥INV, 15–17, 4+♥
1♣-(1♦)-1♥-
1♣-(1♥)-X-
7+, 4+♠
1♠SUPP, 12–17, 3=♠
2♦!FG, 3+♠
2♠MIN, 12–14, 4=♠
3♠INV, 15–17, 4+♠

The cuebid is a useful tool to ask for stopper by ceding notrump declaration. I decide to have a dual meaning 2♥, similar to 4SF. It asks for a stopper by default. Rebidding the suit shows a natural suit.

1♣-(1♥)-X-7+, 4+♠
2♥!INV+, ask for stopper. FG, 5+♥
3♥!FG, 5+♦, 5+♣

Direct and transfer to 1NT

1♣-(*)-1♠-TRF to 1NT, 7+
1NTBAL MIN, 12–14
1♣-(*)-1♠NT-Direct and TRF to 1NT
2♣MIN, 12–14, 6+♣
2♦!INV+ (R), ask for minor suit
2♥♠FG, 5+#
2NTBAL INV
3♣♦FG, 6+#

The 2♦ relay here is nothing more than 1♣-1NT-2♦.

1♣-(*)-1♠; 2♦-INV+ (R)
2♥!5–6♣
2♠!5–6♦
2NTMIN, 2–4♦, 2–4♣
3♣!MAX, 2245
3♦!MAX, 2254
3♥!MAX, 6=♣
3♠!MAX, 6=♦
3NTMAX, 2–4♦, 2–4♣

When opponents bid a major suit, we gain another cuebid to ask for a stopper. It can also be a natural bid like 4SF.

1♣-(1M)-1♠NT-Direct and TRF to 1NT
2M!INV+, ask for stopper. FG, 5+#

Bidding hearts over (1♠)

There is a debate whether free bids are forcing. I prefer negative free bids for major suits and standard forcing free bids for minor suits. I believe this set of agreements maximizes our chances to reach 4♥ and 3NT.

4=♥5=♥6=♥7+♥
7–9XX/2♥2♥3♦
10–11X2♥2♥4♥
FGXX3♦3♦
  1. Invitation is suspectible to interference. Therefore, invitation requires quick actions.
  2. To make best use of non-forcing 2♥, include weaker hands with longer or better suit.
  3. The direct 4♥ not only deters inferference but also splits the range of 3♦.
1♣-(1♠)-X-NEG, 4+♥
2♦!INV+, 3+♥
2♥MIN, 4+♥
3♥INV, 4+♥
1♣-(1♠)-2♥-NF, 5+♥
2♠!FG, ask for stopper
2NT, 3♥NAT INV
3♣♦FG, usually 6+#
3♠!S/T CAB, ask for CTRL
3NT, 4♥To play, no slam interest
1♣-(1♠)-3♦-PRE 7+♥ or FG 6+♥
3♥, 3NTP/C, 0–2♥
3♠!F, NAT or ask for CTRL
4♣♦!F, NAT or CTRL
4♥To play, no slam interest
5♥!Ask for ♠ CTRL

Competing at the 2-level

Competition at 1♣-(*) share properties of the following auctions:

  • (*), as opener shows no suit yet
  • 1NT-(*), as opener shows only strength

1♣-(1NT)

I recommend a transfer system below 3NT. Since X frees up 2NT, 2NT and above become transfers (cf. Rubens advances). Below 2NT, continuations to 1NT form a major-oriented structure. Such structure allows bidding a 5-card major regardless of strength.

1♣-(1NT)--
XPEN, nearly BAL INV+
2♣!STAY. Garbage STAY. INV 5=♠
2♦!TRF, 5+♥
2♥!TRF, 5+♠
2♠!Minor suit Multi/STAY, 6+m or FG 4+♦ 4+♣
2NT!TRF, PRE 7+♣ or FG 6+♣
3♣!TRF, PRE 7+♦ or FG 6+♦
3♦!TRF, PRE 7+♥ or FG 6+♥
3♥!TRF, PRE 7+♠ or FG 6+♠
3♠!Gambling, SOL 7+ suit with no stopper outside
3NT!Gambling, SOL 7+ suit with one stopper outside

1♣-(2♣)

Similar to 1NT-(2♣︎), some 1♣︎-(2♣︎) show both major suits, e.g. Landy, Michaels. This kind of 2♣︎ requires extra care. I recommend BTU vs Unusual.

1♣-(2♣)-Both majors
XPEN for either major
2♦NF, 5+♦
2♥!FG, 5+♦
2♠!INV+, 5+♣
2NT!LEB, PRE 6+♣ or FG (xx)45
3♣♦INV, 6+#
3♥♠!Ask for stopper in this suit

Otherwise, keep using the major-oriented system at 1♣︎-(1NT). This treatment is the same as the systems on approach at 1NT-(2♣︎).

1♣-(2♣)-Other cases
X!INV+ STAY or INV 5=♠
2♦!TRF, 5+♥
2♥!TRF, 5+♠
2♠!Minor suit Multi/STAY, 6+m or FG 4+♦ 4+♣
2NT!TRF, PRE 7+♣ or FG 6+♣
3♣!TRF, PRE 7+♦ or FG 6+♦
3♦!TRF, PRE 7+♥ or FG 6+♥
3♥!TRF, PRE 7+♠ or FG 6+♠
3♠!Gambling, SOL 7+ suit with no stopper outside
3NT!Gambling, SOL 7+ suit with one stopper outside

1♣-(2♦♥♠)

Rubinsohl covers these auctions. FunBridge also inspires the Strawberry adjunct over 1m-(2M):

1♣-(2M)--
3♥!FG, 5=oM
3♥-3♠!Ask for stopper
3♠!FG, 6+oM
The screenshot from FunBridge game engine specifications (requires login)

Natural 1♦

This opening shows 4+♦ and usually 5+♦. It gets more unbalanced as the strength increases.

StrengthDistribution
12–145+♦ or 4♦(441)
15–17UNBAL, 5+♦ or 4♦(441)
18–20UNBAL, 5+♦, 0–3♠, 0–3♥

Unlike Polish Club 2020, I use standard (i.e. non-inverted) minor raises along with mixed raises to maximize preemption. This method utilized the frequent 5th diamond in the 1♦ opening.

Note that 1♦-2♣ is sometimes a phony suit. It is the only way to bid a game-forcing hand with long diamonds and no side major suit.

1♦-12–20, 5+♦ or 4♦(441)
1♥F, 4+♥, usually 6+
1♠F, 4+♠, usually 6+
1NTNF, 6–10, 4+♣
2♣FG, 4+♣ or 4+♦
2♦NF, 6–10, 3+♦
2♥!P/C, 7–9, 4+♥, 5+♠
2♠!UNBAL INV, 4+♦ or 6+♣
2NTBAL INV, 10–11
3♣!CONST, 7–9, 4+♦
3♦PRE, 4–6, 4+♦
3♥!FG SPL, 0–1♥, 0–3♠, 4+♦
3♠!FG SPL, 0–1♠, 0–3♥, 4+♦
3NT12–15, 1–3♠, 1–3♥

P-1♦

Game forcing 2♣ becomes a natural invitation. Consequently, 2♠ is a limit raise because it no longer takes care of clubs.

P-1♦-12–20, 5+♦ or 4♦(441)
2♣INV, 5+♣, 0–3♠, 0–3♥
2♠!LIM, 3+♦

Natural 1♦-1M

The responses 1♦-1♥♠ show 4+ cards just like any 5-card major system. Responder has 6+ points most of the time, but sometimes responder bids with a freaky hand, especially with a long major suit and short diamonds.

1♦-1♥-4+♥
1♠12–17, 4+♠, 5+♦
1NTBAL 12–14, 5=♦
2♣12–17, 4+♣, 5+♦
2♦12–17, 6+♦
2♥12–14, 4+♥
2♠!ART REV, 15–17, 6+♦, 3=♥
2NT18–20, 0–2♥
3♣15–17, 5+♣, 5+♦
3♦15–17, 6+♦, 0–2♥
3♥INV, 15–17, 4+♥
3♠!FG, 18–20, 3=♥
3NTSOL 7+♦, partial stops in ♠ and ♣
1♦-1♠-4+♠
1NT12–14, 4–5♦
2♣12–17, 4+♣
2♦12–17, 6+♦
2♥!REV, 15–17, 4+♥ or 6+♦ 3=♠
2♠12–14, 4+♠ or 3451
2NT18–20, 0–2♠
3♣15–17, 5+♣
3♦15–17, 6+♦, 0–2♠
3♥!FG, 18–20, 3=♠
3♠INV, 15–17, 4+♠
3NTSOL 7+♦, partial stops in ♥ and ♣

BTU 3-way checkback

We use BTU-style 3-way checkback to an XYZ auction. There are 3 artificial relays in the 3-way checkback:

  • 2♣: several variants:
    • to play 2X
    • strongly shaped invitation
    • balanced invitation or choice of games
  • 2♦: game-forcing checkback, usually a choice of games
  • 2NT: transfer to clubs

As a corollary, natural 2X are wide-range invitations and 3X become slam tries.

1♦-1♥-1♠

1♦-1♥-1♠-12–17, 4+♠
1NTMIN, 0–3♠, 4–5♥, 0–3♦
2♣!BTU CB, F1
2♦!FG CB
2♥INV, 5+♥
2♠INV, 4+♠
2NT!TRF, PRE or FG, 6+♣
3♣S/T, 5+♣, 5+♥
3♦S/T, 4+♦, 5+♥
3♥S/T, 6+♥
3♠S/T, 4+♠
1♦-1♥; 1♠-1NTNAT MIN
2♣NF, 4=♣
2♦NF, 6+♦
2♥INV, 3=♥
2♠INV, 5+♠, 6+♦
2NTNAT INV
3♣FG, 4=♣
3♦FG, 6+♦
3♥FG, 3=♥
1♦-1♥; 1♠-2♣BTU CB
2♦MIN
2♥MAX, 3=♥
2♠MAX, at most partial stop in ♣
2NTMAX, likely stop in ♣
3♣MAX, 4054
3♦MAX, 6+♦
1♦-1♥; 1♠-2♣; 2♦-MIN
2♥S/O, UNBAL 5+♥
2♠S/O, 4+♠
2NTBAL INV
3♣INV, 6+♣
3♦INV, 4+♦
3♥INV, S-SOL 6+♥
3♠INV, 4+♠, 5+♥

1♦-1♥-1NT

1♦-1♥-1NT-BAL MIN
2♣!BTU CB, F1
2♣-2♦P/C
2♣-2♥MAX, 3=♥
2♦!FG CB
2♥INV, 5+♥
2♠INV, 4+♠
2NT!TRF, PRE or FG, 6+♣
3♣S/T, 5+♣, 5+♥
3♦S/T, 4+♦, 5+♥
3♥S/T, 6+♥
3♠!SPL, 0–1♠, 6+♥
4♣!SPL, 0–1♣, 6+♥
4♦FG, 4+♦, 6+♥
1♦-1♥; 1NT-2♣; 2♦-P/C
2♥S/O, 5+♥
2♠INV, 4+♠, 6+♥
2NTBAL INV
3♣INV, 6+♣
3♦INV, 4+♦
3♥INV, S-SOL 6+♥

1♦-1♠-1NT

1♦-1♠-1NT-BAL MIN
2♣!BTU CB, F1
2♣-2♦P/C
2♣-2♥MAX, 4+♥
2♣-2♠MAX, 3=♠
2♦!FG CB
2♥INV, 4+♥, 5+♠
2♠INV, 5+♠
2NTTRF, PRE or FG, 6+♣
3♣S/T, 5+♣, 5+♠
3♦S/T, 5+♦, 5+♠
3♥S/T, 5+♥, 5+♠
3♠S/T, 6+♠
3NT12–15, 4=♠
4♣!SPL, 0–1♣, 6+♠
4♦FG, 4+♦, 6+♠
4♥!SPL, 0–1♥, 6+♠
1♦-1♠; 1NT-2♣; 2♦-P/C
2♥MIN, 4+♥, 5+♠
2♠S/O, 5+♠
2NTBAL INV
3♣INV, 6+♣
3♦INV, 6+♦
3♥INV, 5+♥, 5+♠
3♠INV, S-SOL 6+♠

Reverses and Lebensohl

For a precise game try, we sacrifice 2NT as Lebensohl to park minimum hands.

1♦-1♥-2♠-INV, 3=♥, 6+♦
2NT!LEB, MIN
3♣!“4SFG”, ask for 3=♠ or stopper
3♦FG, 2+♦
3♥FG, 6+♥
3♠FG, 6+♠
1♦-1♠-2♥-INV, 4+♥ or 3=♠ 6+♦
2♠NF, 5+♠
2NT!LEB, MIN
2NT-3♣!4+♥
2NT-3♦6+♦, 3=♠
3♣!4SFG
3♣-3♦6+♦, 3=♠
3♣-3♥4+♥
3♦FG, 3+♦
3♥FG, 4+♥
3♠FG, 6+♠

Game-forcing 2♣

The 2♣ response is considered 2/1 FG in this bidding system. It either is natural or conceals a fit in diamonds.

1♦-2♣-FG, 4+♣ or 4+♦
2♦MIN, 12–15, 5+♦ or (41)44
2♥S/T, 15–17, 4+♥
2♠S/T, 15–17, 4+♠
2NTS/T, 14–17, 4441
3♣S/T, 15+, 4+♣
3♦S/T, 15+, 6+♦
3♥!SPL, 12–14 or 18–20, 0–1♥, 0–3♠, 4+♣
3♠!SPL, 12–14 or 18–20, 0–1♠, 0–3♥, 4+♣
3NTMIN, 12–14, 4441

Flannery 2♥

Like 1♣-2♥, 1♦-2♥ is Reverse Flannery. It shows constructive 4+♥, 5+♠.

1♦-2♥-CONST, 4+♥, 5+♠
P, 2♠S/O
2NT!LEB
3♣!FG, 2+♠
3♦!FG, 3+♥
3♥INV, 4+♥
3♠INV, 3+♠
3NTS/O

BTU Ekren + Lebensohl becomes even more useful after the 1♦ opening. When opener wants to play 3m, they can have either long diamonds or a two suiter in minor suits. Responder assumes a 5-5 two suiter first, and then opener can pass or correct.

1♦-2♥-2NT-LEB
3♣3–4♣, 0–1♦, 54(xx)
3♦2–4♦, 0–2♣, 54(xx)
3♥5+♥
3♠6+♠
1♦-2♥-3♣-FG, 2+♠
3♦!54(xx), at most partial stop in ♣
3♥5+♥
3♠6+♠
3NT54(xx), likely stop in ♣
1♦-2♥-3♦-FG, 3+♥
3♥!54(xx), at most partial stop in ♣
3♠6+♠
3NT54(xx), likely stop in ♣

Unbalanced 2♠

The 1♦-2♠ response shows an unbalanced invitation weary of 2NT. It promises either 4+♦ or 6+♣.

1♦-2♠-UNBAL INV
2NT!P/C, MIN 0–1♣
3♣!P/C, MIN 2–3♣
3♦!P/C, MIN 4+♣
3♥!FG, ask for ♠ stopper
3♠!FG, ask for ♥ stopper
3NTS/O

P-1♦-2♠

Passed hand has 2♣ for a club invitation, so 2♠ reduces to a limit raise.

P-1♦-2♠-LIM, 3+♦
2NTMIN, 4=♦
3♦S/O, 5+♦
3♣♥♠FG, 3+#

Competing at the 1-level

This part shares similarities with the 1♣ opening. There are also differences since 1♦ shows a long suit that allows further preempts.

Like 1♣-(X), natural 1NT is not very useful after a double. Transfer to clubs instead. Unlike 1♣-(X), there is no space for Transfer Walsh here.

1♦-(X)--
XXNF BAL G/T, 10+
1MF, 6+, 4+#
1NT!TRF, 6+, 5+♣
2♣!CONST+, 8+, 3+♦
2♦PRE, 0–7, 3+♦
2MPRE, 0–7, 6+#
2NT!TRF, PRE 7+♣ or FG 6+♣
3♣!INV+ TRF, 4+♦
3♦PRE, 0–7, 4+♦
3M!, 4♣!SPL, 0–1#, 4+♦

When RHO bids a major suit, natural notrump from Polish Club 2005 right-sides the contract. Spades below 3NT are transfer cuebids.

1♦-(1M)--
1NTBAL INV, 9–11
2♣INV+, 10+, 5+♣
2♦NF, 6–10, 3+♦
2♠!TRF, PRE 7+♣ or FG 6+♣
2NTFG with stopper
3♣!CONST, 7–9, 4+♦
3♦PRE, 4–6, 4+♦
3♠!Gambling, SOL 7+♣ without stopper
3NT!Gambling, SOL 7+♣ with stopper
4oMTo play
4M!S/T, ask for CTRL

Transfer Walsh only applies to 1♦-(1♥), the only 1-level red suit.

1♦-(1♥)--
X!TRF, 6+, 4+♠
1♠!TRF to 1NT, 6+
2♥!TRF, PRE or INV+, 6+♠
3♥!TRF, PRE 7+♠ or FG 6+♠

Hearts to 1♦-(1♠) are natural.

1♦-(1♠)--
X!TRF, 6+, 4+♥
2♥NF, 6–11, 5+♥
3♥FG, 6+♥

Competing at the 2-level

Major-oriented transfer system competes well with (1NT).

1♦-(1NT)--
XPEN, nearly BAL INV+
2♣!TRF, 3+♦
2♦!TRF, 5+♥
2♥!TRF, 5+♠
2♠!TRF, 5+♣
2NT!TRF, PRE 7+♣ or FG 6+♣
3♣!TRF, PRE 7+♦ or FG 6+♦
3♦!TRF, PRE 7+♥ or FG 6+♥
3♥!TRF, PRE 7+♠ or FG 6+♠
3♠!Gambling, SOL 7+ suit with no stopper outside
3NT!Gambling, SOL 7+ suit with one stopper outside

As clubs are directly under diamonds, bidding after 1♦-(2♣) is pretty natural.

1♦-(2♣)--
X!T/O, INV+
2♦CONST, 3+♦
2MNF, 5+#
2NTNAT INV
3♣!INV+, 4+♦
3♦PRE, 4+♦
3MFG, usually 6+#

Competition with 1♦-(2M) models after Rubinsohl. The forcing raise 3♣ and the preemptive raise 3♦ weaponize the diamond fit. The Strawberry adjunct applies here just like 1♣-(2M).

1♦-(2M)--
X!OPT, INV+
2♠NF, 5+♠
2NT!TRF, 5+♣
3♣!INV+, 3+♦
3♦PRE, 4+♦
3♥!FG, 5=oM
3♥-3♠!Ask for stopper
3♠!FG, 6+oM

Natural 1♥

The major suit openings show 12–17 points and 5+ cards. I separate them into two chapters due to subtle differences in their continuations.

Responses to 1♥ are similar to natural 2/1 along with mixed fit-showing jumps.

1♥-12–17, 5+♥
1♠F, 4+♠
1NTNF, usually 7–11, 0–3♠, 0–3♥
2♣♦NAT FG
2♥CONST, 3+♥
2♠!NF, 6+♠: CONST 3+♥ or INV 0–2♥
2NT!FG, 4+♥
3♣♦!CONST+, 5+#, 4+♥
3♥LIM, 4+♥
3♠!SPL, 0–1♠, 4+♥
3NT!Choice of games, 12–15, 33(43)
4♣♦!SPL, 0–1#, 4+♥
4♥!PRE, UNBAL 4+♥

Plans to invite with spades

  • The best invitations go through CB and jump to the 3-level, e.g. 63(xx), 54(xx)
  • Balanced invitations go through CB and bid directly at the 2-level.
  • Distributional mild invitations go to 2♠.

1♥-2♠

This jump shift tries to tackle hands hard to describe with BTU CB. It shows 6+♠ with either extra values or a heart fit, but not both. With both features, 1♥-1♠-1NT is the happy path since it ensures a double fit.

1♥-2♠-NF, 6+♠
2NT!(R)
3♣MAX, 5+♣
3♦MAX, 5+♦
3♥!P/C, somewhat PRE
3♠!P/C, invite 3+♥
3NT!P/C to 4♥ with 3+♥
4♣!STR choice of games
4♦!PRE choice of games
4♥♠To play

P-1♥

P-1♥ reduces to a fairly natural system. We can keep using Stenberg 2NT because it assigns minimum hands to 3♣.

P-1♥-12–17, 5+♥
2♣♦INV, 5+#
2NT!INV, 4+♥
3♥!CONST, 4+♥

Natural 1♥-1♠

As the opening is limited to 12–17, the reverses are not forcing. The reverses show a maximum 5+ 5+ two suiter.

1♥-1♠-4+♠
1NTBAL 12–14
2♣♦NF, 4+#
2♥MIN, 12–14, 6+♥
2♠MIN, 12–14, 4+♠
2NTBAL INV, 15–17
3♣♦INV, 15–17, 5+#
3♥INV, 15–17, 6+♥
3♠INV, 15–17, 4+♠
3NTTo play
4♣♦!SPL, 0–1#, 4+♠
4♥♠To play

BTU 3-way checkback

BTU checkback is also in effect after 1♥-1♠-1NT, similar to 1♦-1M-1NT. There are 3 artificial relays in the 3-way checkback:

  • 2♣: several variants:
    • to play 2X
    • strongly shaped invitation
    • balanced invitation or choice of games
  • 2♦: game-forcing checkback, usually a choice of games
  • 2NT: transfer to clubs

As a corollary, natural 2X are wide-range invitations and 3X become slam tries.

1♥-1♠-1NT-BAL MIN
2♣!BTU CB, F1
2♣-2♦P/C
2♣-2♥!P/C, 4+♦
2♣-2♠!MAX, 3=♠
2♦!FG CB
2♥INV, 2–3♥
2♠INV, 5+♠
2NT!TRF, PRE or FG, 6+♣
3♣S/T, 5+♣, 5+♠
3♦S/T, 5+♦, 5+♠
3♥S/T, 3+♥
3♠S/T, 6+♠
1♥-1♠; 1NT-2♣; 2♦-P/C
2♥S/O, 2+♥
2♠S/O, 5+♠
2NTBAL INV
3♣INV, 6+♣
3♦INV, 6+♦
3♥INV, 4+♥, 5+♠
3♠Choice of games, 6+♠, 3+♥

Non-forcing 1NT

Opener is free to pass 1♥-1NT with a balanced minimum. The best major fit at 1♥-1NT-P is balanced 5-3. Opener can judge when to pass quite safely.

The 2♣ rebid promises 3+♣ like Wbridge5 to ensure a safe courtesy raise.

1♥-1NT-Usually 7–11, 0–3♠, 0–3♥
2♣NF, 3+♣
2♦NF, 4+♦
2♥MIN, 6+♥
2♠MAX, 4+♠
2NTBAL MAX
3♣♦MAX, 5+#
3♥MAX, 6+♥
3♠MAX, 4+♠, 6+♥

Impossible spades

As 1NT denies 4+♠, the 2♠ rebid must be artificial. The impossible 2♠ is a forcing raise that is stronger than a courtesy raise.

1♥-1NT-2♣-NF, 3+♣
2♦NF, 5+♦
2♥NF, usually 2–3♥
2♠!STR INV, 4+♣
2NTBAL INV
3♣Mild INV, usually 5+♣
3♦INV, 6+♦
3♥INV, 3=♥
1♥-1NT-2♦-NF, 4+♦
2♥NF, usually 2–3♥
2♠!STR INV, 4+♦
2NTBAL INV
3♣INV, 6+♣
3♦Mild INV, 4+♦
3♥INV, 3=♥

Game-forcing 2♣♦

Unpassed 2/1 is 100% game-forcing. Opener defaults to rebid 2♥. Opener’s reverses promise extra strength.

1♥-2♣-NAT FG
2♦4+♦
2♥MIN
2♠MAX, 4+♠
2NTBAL MAX
3♣MAX, 4+♣
3♦MAX, 5+♦
3♥MAX, 6+♥
3♠!MIN SPL, 0–1♠, 4+♣
3NTMIN, 3532
1♥-2♦-NAT FG
2♥MIN
2♠MAX, 4+♠
2NTBAL MAX
3♣MAX, 4+♣
3♦MAX, 4+♦
3♥MAX, 6+♥
3♠!MIN SPL, 0–1♠, 4+♦
3NTMIN, 3523

Modified Stenberg 2NT

The principle of fast arrival should not apply to an unlimited Jacoby 2NT. The weaker opener is, the more likely responder has something to say. Therefore, we import responses from Stenberg AKA Swedish Jacoby 2NT.

1♥-2NT-FG, 4+♥
3♣!MIN
3♦!MAX, no SPL
3♥!MAX FRAG, 0–1♣
3♠!MAX FRAG, 0–1♦
3NT!MAX FRAG, 0–1♠
4♣MAX, 5+♣
4♦MAX, 5+♦
4♥!MAX, 6+♥, 4+♠
1♥-2NT-3♣-MIN
3♦!Ask for distribution
3♥S/T
3NTBAL choice of games
1♥-2NT; 3♣-3♦-Ask for distribution
3♥!FRAG, 0–1♣
3♠!FRAG, 0–1♦
3NT!FRAG, 0–1♠
4♣5+♣
4♦5+♦
4♥Nearly BAL

Natural 1♠

The major suit openings show 12–17 points and 5+ cards. I separate them into two chapters due to subtle differences in their continuations.

  • Unpassed 1♠-1NT is forcing.
  • Maggie 1♠-2♣ is either a natural game force or a heart invitation.
  • Fit-showing jumps show mixed raises. Major-over-major jumps are 6-3 instead of 5-4 for more choices.
1♠-12–17, 5+♠
1NTF, usually 7–11, 0–3♠
2♣!NAT FG or INV 5–6♥
2♦FG, 4+♦
2♥FG, 5+♥
2♠CONST, 3+♠
2NT!FG, 4+♠
3♣♦!CONST+, 5+#, 4+♠
3♥!INV, 6+♥, 3=♠
3♠LIM, 4+♠
3NT!Choice of games, 12–15, 33(43)
4X!SPL, 0–1#, 4+♠
4♠PRE, UNBAL 4+♠

Responding with 5+ hearts

  • Game-forcing: 2♥
  • Strong invitational 6+ hearts: 1NT and then 3♥
  • Invitational: 2♣
  • Constructive: 1NT and then 2♥

P-1♠

P-1♠ reduces to a fairly natural system. We can keep using Stenberg 2NT because it assigns minimum hands to 3♣.

P-1♠-12–17, 5+♠
1NTNF, usually 7–11, 0–3♠
2♣♦♥INV, 5+#
2NT!INV, 4+♠

Forcing 1NT

Unpassed 1♠-1NT is forcing to accommodate strong invitations, especially 6+♥, which is one step away from 4♥.

1♠-1NT-Usually 7–11, 0–3♠
2♣NF, 4+♣ or BAL MIN
2♦NF, 4+♦
2♥NF, 4+♥
2♠MIN, 6+♠
2NTBAL MAX
3♣♦♥MAX, 5+#
3♠MAX, 6+♠

Maggie 2♣

Unlike 1♥-1NT, 1♠-1NT my conceal a heart fit. Finding a 3-5 fitted 4♥ after 1♠-1NT is pretty challenging. Bart is a convention after forcing 1NT that tries to tackle heart invitation. Lisa, Bart’s smarter sister, is an improvement of Bart. Maggie, the youngest Simpson, solves this problem at 1♠-2♣ instead.

Given a natural 2/1 bidding system, 1♠-2♣-2♦♥ are underused. These steps are a better place for a convention than inside the crowded 1♠-1NT.

1♠-2♣-NAT FG or INV 5–6♥
2♦!MIN (R), 12–14, 0–3♥
2♥!MIN P/C, 12–13, 2–3♥
2♠!FG, MIN 4+♥
2NT!MAX, 3-4♥
3♣MAX, 4+♣, 0–2♥
3♦MAX, 5+♦, 0–2♥
3♥MAX, 5+♥
3♠MAX, 6+♠, 0–2♥
3NTMAX, 5=♠︎, 1–2♥, 3–4♦, 2–3♣
4♣!MIN FRAG, 0–1♦, 3+♥, 4+♣
4♦!MAX SPL, 0–1♦, 3+♥, 4+♣
  • 2♥: To play for an invitation.
  • 2♦: Not to play 2♥ for an invitation:
    • 13–14 that wants to play a game
    • 12–13 that wants to sign off at 2-level
1♠-2♣-2♦-MIN (R)
2♥NF S/P, 6=♥ or 0–1♠
2♠NF S/P, 2+♠
2NT+NAT FG
1♠-2♣-2♥-MIN P/C
2♠NF, 3=♠
2NT+NAT FG

Compared with the default 1♠-2♣-2♠ in 2/1, Maggie occupies no more space. Non-forcing sequences only take space up to 2♠.

Game-forcing 2♦♥

Unpassed 2/1 is 100% game-forcing. Opener defaults to rebid 2♠. Opener’s reverses promise extra strength.

1♠-2♦-FG, 4+♦
2♥4+♥
2♠MIN
2NTBAL MAX
3♣MAX, 4+♣
3♦MAX, 4+♦
3♥MAX, 5+♥
3♠MAX, 6+♠
3NTMIN, 5323
1♠-2♥-FG, 5+♥
2♠MIN
2NTBAL MAX
3♣MAX, 4+♣
3♦MAX, 4+♦
3♥MAX, 3+♥
3♠MAX, 6+♠
3NTMIN, 5233
4♣♦!MIN SPL, 0–1#, 4+♥
4♥MIN, 53(xx)

Modified Stenberg 2NT

The principle of fast arrival should not apply to an unlimited Jacoby 2NT. The weaker opener is, the more likely responder has something to say. Therefore, we import responses from Stenberg AKA Swedish Jacoby 2NT.

1♠-2NT-FG, 4+♠
3♣!MIN
3♦!MAX, no SPL
3♥!MAX FRAG, 0–1♣
3♠!MAX FRAG, 0–1♦
3NT!MAX FRAG, 0–1♥
4♣MAX, 5+♣
4♦MAX, 5+♦
4♥MAX, 5+♥
4♠!MIN, 5+♥
1♠-2NT-3♣-MIN
3♦!Ask for distribution
3♠S/T
3NTBAL choice of games
1♠-2NT; 3♣-3♦-Ask for distribution
3♥!FRAG, 0–1♣
3♠!FRAG, 0–1♦
3NT!FRAG, 0–1♥
4♣5+♣
4♦5+♦
4♥5+♥
4♠Nearly BAL

Ekren 2♣

Ekren is an artificial preempt showing 4+ cards in each major. It is originally at 2♦. Polish Club 2020: Expert moves it to 2♣ to replace Precision 2♣ and leaves space for Multi.

2♣-PRE, 4+♠, 4+♥
2♦!F, ask for the better major suit
2NTNAT NF, usually long ♦
3♣NAT F
3♦NAT F
4♣!STR choice of games
4♦!PRE choice of games
2♣-2♦-Ask for the better major
2♥♥ ≥ ♠
2♠♠ > ♥
2NT!ART, 5+♠, 5+♥
3♣!MAX SPL, 0–1♣, 5+♠, 5+♥
3♦!MAX SPL, 0–1♦, 5+♠, 5+♥
3♥6+♥
3♠6+♠

There are two kinds of choice of games:

  • 4♣ by strength
  • 4♦ by distribution

Such distinction helps judging how to react to interference. Besides, 4♣ lets the strong hand declare. On the other hand, 4♦ closes the auction ASAP.

2♣-4♣-STR choice of games
4♦!TRF, ♥ ≥ ♠
4♥!TRF, ♠ > ♥
2♣-4♦-PRE choice of games
4MTo play

Blueberry Cottontail Club

This bidding system is a hybrid between a modernized Blue Club and Larsson’s Cottontail Club.

-
1♣!STR ART, 16+
1♦!NF, 11–15, 2+♦
1♥11–15, 4+♥, no BAL MAX 4=♥
1♠11–15, 4+♠, no BAL MAX 4=♠
1NT11–13:
2–3♠, 2–3♥, 2–6♦, 2–6♣.
(4333).
2♣11–15, 6+♣ or MIN 4M5♣
2♦!PRE, 6+M
2M!PRE, 5=#, 4+m
2NT!UNT, 5+♦, 5+♣
3XPRE, 7+#
3NT!Gambling, SOL 7+m, 0–1 outside A/K
4♣!PRE, S-SOL 8+M, 0–1 outside A/K
4♦!PRE, SOL 8+M, no outside A/K
4MPRE, 8+#
4NT!UNT, 6+♦, 6+♣

The notrump ladder

  • 11–13: 1NT
  • 14–15: 1♦-1♥♠; 1NT
  • 16–18: 1♣-1♦; 1NT
  • 19–21: 1♣-1♦; 1♥-1♠; 1NT
  • 22–23: 1♣-1♦; 1♥-1♠; 2NT
  • 24+: 1♣-1♦; 2NT

Blueberry Gazzilli

Another recurring pattern in this bidding system is generalized Lauria-style Gazzilli.

  • Our last two bids are 1M-1NT or 1♥-1♠ (Kaplan interchange), a natural major suit followed by a suitless response.
  • Rebidding the major suit does not show extra length. It shows a predefined side suit instead (not necessarily clubs).
  • A low rebid (1NT or 2♣) becomes a relay:
    • Extra length in the major suit is possible.
    • Extra strength is possible.
    • The relay can be non-forcing because many bids in this system are fairly limited.

Strong 1♣

Blueberry employs a novel approach to the strong club opening bid. The 1♥ response is an immediate double negative. This approach is well known for the strong 2♣ opening in natural systems, but it is uncommon for strong 1♣ systems. This pioneering method has two main goals:

  1. 1♣-1♦-1♥ is forcing and accommodates steps on the notrump ladder.
  2. 1♣-1♥ proposes playing 1♥, more powerful than playing 1♦.

The cost is that 1♦ is now forcing, the contract we seldom play even if opponents ever let us. The 1NT response also sporadically wrong-sides the notrump contract. I find slowly showing strong balanced hands OK since these hands are slow in competition anyway.

1♣-STR ART, 16+
1♦!(R)
1♥!DBL NEG, 0–4, 0–5♠, 0–4♥, 0–6♦, 0–6♣
1♠FG, 4+♠
1NT!FG, 5+♥
2♣FG, 5+♣
2♦FG, 5+♦
2♥INV, 4–7, 6+♥
2♠INV, 4–7, 6+♠
2NT!INV, 5–7, 5+♦, 5+♣
3♣INV, 5–7, 7+♣
3♦INV, 5–7, 7+♦
3♥!INV, 5–7, 5+♥, 5+♠

BTU 1NT

This bidding system has a strong notrump opening that does not contain a 5-card major. We use the BTU continuations after the 1NT opening: Stayman takes care of invitation with 5+ spades.

1NT-BAL 15–17
2♣!STAY. Garbage STAY. INV 5=♠
2♦!TRF, 5+♥
2♥!TRF, 5+♠
2♠!Minor suit Multi/STAY, 6+m or FG 4+♦ 4+♣
2NTNAT INV
3♣INV, 6+♣, KQxxxx or better, usually 6–7 HCP
3♦INV, 6+♦, KQxxxx or better, usually 6–7 HCP
3♥!INV, 5+♠, 5+♥
3♠!Choice of games, 5+♠, 5+♥
3NTS/O
4♣!Gerber BW
4♦!Texas TRF, 6+♥
4♥!Texas TRF, 6+♠
4♠!F QUANT
4NTQUANT INV to 6NT, NF
5NTQUANT INV to 7NT, F

BTU QUANT scheme

BTU reuses 4♠ for QUANT. This fills the blank that Gerber and Texas leave. Standard QUANT usually invites the upper 1/2 to 2/3 of the opening range. This 4♠ serves as a narrower QUANT than 4NT or 5NT by only inviting the top 1/3.

1NT-4NT-QUANT INV to 6NT
6NTS/O, 16–17 HCP
1NT-5NT-QUANT INV to 7NT
6NTS/O, 15 HCP
7NTS/O, 16–17 HCP
1NT-4♠-F QUANT
4NT15–16 HCP
4NT-5NT!F to a 5-card suit or 6NT
4NT-7♣!P/C to a 5-card suit or 7NT
6NT17 HCP

Discussion on bidding 5-5 majors

There are 3 ways to bid 5-5 majors in BTU 1NT: 3♥♠ and via transfers. There is more than one version in BTU. I am demonstrating my recommendation here step by step.

There are 4 levels of 5-5 majors: weak, invitational, choice of games, and slam try.

  • Weak: transfer to the better major and pass. Give up on the other one.
  • Invitational: anything goes except 3♠.
  • FG+: anything goes.

Hands around the game level are prone to interference. On the other hand, leaking opener’s shape can be helpful in slam bidding. As a result, I recommend the following bidding structure:

  • Invitational: 3♥
  • Choice of games: 3♠
  • Slam try: 2♥ and then 3♥

BTU Stayman 2♣

BTU Stayman is characterized by including invitations of 5= spades. All its variants are:

  • Weak: T/O with short clubs (Garbage Stayman)
  • Invitational: 4–5♠ or 4=♥ (BTU)
  • Game-forcing: 4=♠ or 4=♥
1NT-2♣-BTU STAY
2♦!2–3♠, 2–3♥
2♥4=♥, 2–3♠
2♠4=♠, 2–3♥
2NT!MIN, 44(xx)
3♣!MAX, 44(xx)

1NT-2♣-2♦

  • Smolen at both levels takes care of spade invitation.
  • Second responses above 3NT remain the same, assuming misfit.
1NT-2♣-2♦-NEG
2♥!TRF INV, 5+♠
2♠!NF INV Smolen, 4=♠, 5+♥
2NTNAT INV
3♣FG, 5+♣
3♦FG, 5+♦
3♥!FG, Smolen TRF, 54(xx)
3♠!FG, Smolen TRF, 45(xx)
4♣!Gerber BW
4♦!Texas TRF, 6+♥, 4=♠
4♥!Texas TRF, 6+♠, 4=♥
4♠!F QUANT
4NTQUANT INV to 6NT
5NTQUANT INV to 7NT
1NT-2♣; 2♦-2♥-INV, 5+♠
2♠MIN
2NTINV, 2=♠
3♣♦♥!INV, xx in this suit, 3=♠
3♠INV, 3=♠

1NT-2♣-2♥

  • BTU QUANT scheme remains, assuming misfit.
  • 3♠ is a generic fit S/T, so 4NT is QUANT instead of RKCB.
1NT-2♣-2♥-4=♥, 2–3♠
2♠INV, 5+♠
2NTINV, 0–3♥, 4=♠
3♣FG, 5+♣, 0–3♥, 4=♠
3♦FG, 5+♦, 0–3♥, 4=♠
3♥INV, 4+♥
3♠!S/T, 4+♥
4♣♦!S/T SPL, 0–1#, 4+♥
4♠!F QUANT
4NTQUANT INV to 6NT
5NTQUANT INV to 7NT
1NT-2♣; 2♥-2♠-INV, 5+♠
2NTINV, 2=♠
3♣♦♥!INV, xx in this suit, 3=♠
3♠INV, 3=♠

1NT-2♣-2♠

  • Only standard QUANT scheme remains. Now 4♠ is S/O.
  • 3♥ is a generic fit S/T, so 4NT is QUANT instead of RKCB.
1NT-2♣-2♠-4=♠, 2–3♥
2NTINV, 0–3♠, 4=♥
3♣FG, 5+♣, 0–3♠, 4=♥
3♦FG, 5+♦, 0–3♠, 4=♥
3♥!S/T, 4+♠
3♠INV, 4+♠
4♣♦♥!S/T SPL, 0–1#, 4+♠
4♠S/O, 4+♠
4NTQUANT INV to 6NT
5NTQUANT INV to 7NT

BTU transfers 2♦♥

BTU Jacoby transfers are characterized by subsequent forcing relays. Thanks to moving spade invitation to Stayman, we enjoy one more step to separate slam try from choice of games.

Opener super-accepts with maximum 4-card support. To help game try, opener tries to show (4333) or xx in a side suit.

1NT-2♦

Responder rebids forcing 2♠ for a 5=♥ invitation. This forcing bid allows invitation by distribution, e.g. 5=♥ 5+m.

1NT-2♦-5+♥
2♥(R)
2♠!MAX, ♠xx, 4=♥
2NTMAX, 3433
3♣!MAX, ♣xx, 4=♥
3♦!MAX, ♦xx, 4=♥
3♥MAX, 4=♥, none of the above
1NT-2♦-2♥-
2♠!F INV, 5=♥
2NT!UNBAL FG
3♣!S/T, 4+♣
3♦!S/T, 4+♦
3♥INV, 6+♥
3NTBAL P/C
3♠!, 4♣♦!SPL, 0–1#, 6+♥
4♥Mild S/T, 6+♥
4♠!F QUANT
4NTQUANT INV to 6NT
5NTQUANT INV to 7NT
1NT-2♦; 2♥-2♠-INV, 5=♥
2NTMIN, 15 HCP, 2=♥
3♣!P/C, 16 HCP, 2=♥
3♦!P/C, 16 HCP, 2=♥, 5+♣
3♥MIN, 3=♥
3NTS/O, 17 HCP, 2=♥

1NT-2♥

With 5=♠ invitation moved to Stayman, 5=♠ hands here are either weak or game forcing.

1NT-2♥-5+♠
2♠(R)
2NT!MAX, 4333
3♣!MAX, ♣xx, 4=♠
3♦!MAX, ♦xx, 4=♠
3♥!MAX, ♥xx, 4=♠
3♠MAX, 4=♠, none of the above
1NT-2♥-2♠-
2NT!UNBAL FG
3♣!S/T, 4+♣
3♦!S/T, 4+♦
3♥!S/T, 5+♥
3♠INV, 6+♠
3NTBAL P/C
4♣♦♥!SPL, 0–1#, 6+♠
4♠Mild S/T, 6+♠
4NTQUANT INV to 6NT
5NTQUANT INV to 7NT

BTU 2♠

BTU 2♠ combines minor suit Multi and Stayman. Responder has either a 6+ minor suit or both minor suits.

1NT-2♠-Minor suit Multi/STAY
2NT2–3♦, 2–3♣
3♣!P/C, 4+♦
3♦!P/C, 4+♣

Multi 2♦

Multi 2♦ shows a 6-card weak two of either major.

2♦-PRE, 6+M
2MP/C
2NT!INV+ (R)
3♣♦NAT F
3MP/C
3NTS/O
4♣!STR choice of games
4♦!PRE choice of games
4MS/O
2♦-2NTINV+
3♣!MAX, 6+♥
3♦!MAX, 6+♠
3♥MIN, 6+♥
3♠MIN, 6+♠

There are two kinds of choice of games:

  • 4♣ by strength
  • 4♦ by distribution

Such distinction helps judging how to react to interference. Besides, 4♣ lets the strong hand declare. On the other hand, 4♦ closes the auction ASAP.

2♦-4♣-STR choice of games
4♦!TRF, 6+♥
4♥!TRF, 6+♠
2♦-4♦-PRE choice of games
4MTo play, 6+#

Suggested defense: Multi vs Multi

I regard Multi vs Multi as a specialized version of Unusual vs Unusual. X remains “penalizing” either suit but longer. Cuebids are reordered and show unbid (minor) suits.

(2♦)-PRE, 6+M
X!OPT: 12+, 5+M. 15+, (41)44. 19+, 1–4♠, 1–4♥, 1–4♦, 1–4♣.
2♥!BAL, 16–18
2♠!TRF, 14+, 5+♣
2NT!TRF, 14+, 5+♦
3♣NAT, 8–13, 6+♣
3♦NAT, 8–13, 6+♦
3M!NF Michaels, 5+#, usually 5+m

(2♦)-X

Here I recommend a modified version of Rumpelsohl. Frequently pass 2♦x with 4+ diamonds to ease slam exploration, especially for minor suit slams.

(2♦)-X-OPT: either major or 19+
2M!P/C
2NT!INV+, REV LEB
3♣PRE, usually 5+♣
3♦!INV+ TRF, 5+♥
3♥!INV+ TRF, 5+♠
3♠!FG TRF, usually 6+♣
3NTTo play
4♣!STR choice of games
4♦!PRE choice of games
(2♦)-X-2NTREV LEB
3♣!P/C, 12–14
3♦!S/T, 18+
3MNAT, 15–17, 5+#

When RHO bids, X is penalty and usually short in the other major. We play Rubinsohl here because we need to bid diamonds. Please refrain from penalizing with length in both major suits. It is usually better to make our own contract than setting their doubled partscore.

(2♦)-X-(2M)-P/C
XPEN, good 4+# and usually short in the other major
2♠!P/C
2NT!TRF, 5+♣
3♣!TRF, 5+♦
3♦!TRF, 5+oM
3♥!P/C, INV in ♥, INV+ in ♠
3♠!P/C, INV in ♠, FG in ♥
(2♦)-X-(3M)-P/C
XPEN, usuaully short in the other major

After opener shows their major, doubler always penalizes when holding the same suit. This action is mostly safe because doubler sits behind the opener. More importantly, this treatment creates a negative inference that a pass implies holding the other major.

  • (2♦)-X-(2♠); (3♥)-X = Usually hearts
  • (2♦)-X-(2♠); (3♥)-P = Spades!

(2♦)-2♥

Partner is limited and balanced like the 1NT opening. I suggest playing like Rumpelsohl at 2♥x.

(2♦)-2♥-BAL 16–18
PS/O, 4+♥
2♠S/O, 4+♠
2NTLEB, 3+♣ or STAY
3♣!TRF, 5+♦
3♦!TRF, INV+, 5+♥
3♥!TRF, INV+, 5+♠
3♠!TRF, FG, 6+♣

Transfer to minors

The two-under transfers have a non-forcing Herbert negative step as escape.

(2♦)-2♠-14+, 5+♣
2NT!NF NEG, 0–2♣
3♣To play
3♦♥♠NAT F
(2♦)-2NT-14+, 5+♦
3♣!NF NEG, 0–2♦
3♦To play
3♥♠, 4♣NAT F

Muiderberg 2M

Muiderberg shows exactly 5 cards in the bid major and a side minor suit. Multi 2♦ already takes care of 6+ cards.

2MPRE, 5+M, 4+m
2♠NAT NF
2NT!INV+, ask for the minor suit
3♣!P/C
3♦!INV+, 3+M
2M-2NTINV+ (R)
3♣MIN, 4+♣
3♦MIN, 4+♦
3♥!MAX, 4+♣
3♠!MAX, 4+♦

Unusual 2NT opening

The unusual 2NT opening is a preempt with 5+♦ and 5+♣. Bidding all strong hands with 1♣ frees up 2NT as a preempt.

I advise not opening 2NT for (30)55 in the first two seats.

2NT-PRE, 5+♦, 5+♣
3♣♦S/O
3♥!FG (R)
3♠!PUP, S/T or UNBAL INV
3NT, 4XS/O
4NT!Equal preference between 5♣♦
2NT-3♥-FG (R)
3♠!SPL, 0–1♠
3NT!SPL, 0–1♥
4♣MAX 1156
4♦MAX 1165
2NT-3♥-4♣♦-MAX 11(65)
4♥!RKCB in ♣
4♠!RKCB in ♦
4NTS/O
2NT-3♠-3NT-(R)
4♣INV, 3+♣
4♦INV, 3+♦
5♣!S/T, 3+♣
5♦!S/T, 3+♦

BTU Namyats

BTU uses a 4X scheme that conveys ~0.58 more bits than traditional or Meckwell Namyats.

  • 4♣: solid major suit without any outside A/K
  • 4♦: semi-solid major suit with 0–1 outside A/K
  • 4M: non-solid (1.5+ NLTC) major suit
4X-PRE in 4M
4NT!RKCB
5m!CTRL ASK
4X-5m-CTRL ASK
+1No CTRL
+2K or singleton
+3A or void
4♣♦-(S-)SOL PRE in 4M
4♦!S/T (R)
4M, 5M, 6MP/C
4♣-4♦-S/T (R)
4MNAT MIN
4NT!MAX, CTRL in every side suit
5♣!MAX, no CTRL in ♣
5♦!MAX, no CTRL in ♦
5M!MAX, no CTRL in oM
4♥-PRE, non-SOL
4♠S/O

Rubinsohl

Rubinsohl is a bidding convention aiming for competition at the 2-level. Originally, for auctions such as 1NT-(2♦♥♠), use 2NT and some steps above to convey conventional meanings. I am generalizing onset conditions as follows:

  1. Partner has ever bid a non-pass.
  2. Moreover, the last non-pass is (2♦♥♠) by either opponent.

If the last non-pass is an artificial call by partner, such as a takeout double, I recommend Rumpelsohl instead.

Similar to Rubens advances, the transfer structure helps saving bidding space. Showing the suit faster also helps competition.

*-(2♦)--
XOPT
2MNAT NF
2NT!TRF to 3♣
3♣!STAY
3♦!INV+ TRF to 3♥
3♥!INV+ TRF to 3♠
3♠!FG TRF to 3NT or 4♣
*-(2♥)--
XOPT
2♠NAT NF
2NT!TRF to 3♣
3♣!TRF to 3♦
3♦!STAY
3♥!INV+ TRF to 3♠
3♠!FG TRF to 3NT or 4♣

Swap 3♥♠ against (2♠) like Larry Cohen to avoid declaring hearts.

*-(2♠)--
XOPT
2NT!TRF to 3♣
3♣!TRF to 3♦
3♦!TRF to 3♥
3♥!FG TRF to 3NT or 4♣
3♠!FG STAY

Rumpelsohl

Rumpelsohl by Paul van Rijckevorsel was published in The Bridge World, October 1992. Traditionally, (2X)-X also start Lebensohl. However, artificial calls, even limited ones, are not meant to be passed with boring hands. I decide to modify the bidding structure for this subtle difference.

  1. The last bid is 2♦♥♠
  2. The last non-pass is an artificial call by partner.

In this section, I list (2X)-X as examples. The meaning of each step varies with partner’s call. There are several reasons to invite with 2NT.

  • Bidding to (2X)-X is not free.
  • An invitational X usually lacks a stopper.

Therefore, 2NT includes NF clubs and constructive-invitational hands.

(2♦)-X-T/O
2MNAT NF
2NT!LEB: 4+♣ or CONST–INV
3♣!STAY
3♦!INV+, 5+♥
3♥!INV+, 5+♠
3♠!FG, 5+♣
(2♥)-X-T/O
2♠NAT NF
2NT!LEB: 4+♣ or CONST–INV
3♣!TRF, 4+♦
3♦!STAY, 4=♠
3♥!INV+, 5+♠
3♠!FG, 5+♣

Again, Larry Cohen’s adjunct swaps 3♥♠ over (2♠).

(2♠)-X-T/O
2NT!LEB: 3+♣ or CONST–INV
3♣!TRF, 4+♦
3♦!TRF, 4+♥
3♥!FG, 5+♣
3♠!FG STAY, 4=♥

BTU vs Unusual

When opponents have bid two suits, optimists take the opportunity of gaining two cuebids! When opponents have shown two anchor suits, it’s time for Unusual vs Unusual.

The third cuebid

This is one key difference between BTU vs Unusual and literature. The BTU variation uses the lowest three bids from the following list:

  • The cuebids, the bids that name an adverse suit
  • 2NT or 4NT

Let me provide some examples for clarity.

AuctionBTU v U bids
1♦-(2♦ = ♠ + ♥)-2♥, 2♠, 2NT
1♠-(2NT = ♦ + ♣)-3♣, 3♦, 4♣
1♠-(3♣ = ♥ + ♦)-3♦, 3♥, 4♣
2♥-(4♦ = ♠ + ♦)-4♠, 4NT, 5♦
(1♦)-(1♠)-2♦, 2♠, 2NT
(1♦)-1♥-(X = ♠)1♠, 2♦, 2♠

The BTU v U bids are abbreviated as Q1, Q2, Q3 to facilitate discussion. If the cuebid is 4NT or above, I recommend that it start another slam try convention (e.g. RKCB, Turbo) as per partnership discussion.

We have one anchor suit

Rubens advances tell us that a fit requires less space. Therefore, Q1 maps to the new suit, and Q2 is the forcing raise.

  1. Q1 = 5+ new suit
  2. Q2 = forcing raise
  3. Q3 = new suit + mediocre forcing raise

We have 0 or 2 anchor suits

Unlike the intuitive lower-lower approach, BTU v U maps Q1 to the higher-ranking suit.

  1. Q1 = 5+ higher-ranking suit
  2. Q2 = 5+ lower-ranking suit
  3. Q3 = 5+ lower-ranking suit, 4+ higher-ranking suit

Slam bidding

Slam bidding involves a stack of conventions for various situations. I list them from the general to the specific.

  • Italian control bids, which promise 2nd round controls
  • Non-serious 3NT
  • RKCB 1430 for major suits and conventional kickbacks
    • For example, unusual 2NT-4♥♠ is RKCB in ♣♦ respectively
  • Turbo 4NT for minor suits
  • Control asking RKCB

Notation on suit variables

In competitive and defensive bidding, combinations of calls grow factorially. It is convenient to replace unknown suits with variables, just like how algebra brings computation to a higher level.

This book usually follows principles introduced in BML and CSS.

Ordered suit variables

X, Y, Z are suit variables that satisfy X < Y < Z. They are also distinct from the other suits in the same auction. For example:

  • (1Y)-2X matches (1♥)-2♣ but not (1♥)-2♠.
  • (1Y)-2Z matches (1♥)-2♠ but not (1♥)-2♣ or (1♥)-2NT.
  • (1M)-2X matches (1♥)-2♣ but not (1♥)-2♥.

Precedence

Multiple rules may match the same auction. The rule with the highest precedence applies.

Precedence of strain symbols

Concrete strain > suit class > suit variable

  • Concrete strain: ♣, ♦, ♥, ♠, NT
  • Suit class: M, m, R, B
  • Suit variable: X, Y, Z

Juxtaposition of strain symbols

Juxtaposition of strain symbols produces multiple rules, similar to | in regular expression. For example, 2MNT is a valid expression that matches 2♥, 2♠, and 2NT.

Specificity of rules

Specificity is determined like CSS specificity. The rule with the most concrete strains wins. Then we compare the number of suit classes. Note that juxtaposition expands to multiple rules instead of one. For example:

  • 1♥-2X > 1R-2B
  • Comparing 1MNT-2X and 1X-1R:
    • 1M-2X = 1X-1R
    • 1NT-2X > 1X-1R

Precedence of rules

The most specific rule applies. If there are multiple rules with the same specificity, compare specificity lexicographically. For example, 1M-2X > 1X-1R because 1M is more specific than 1X. If there are still multiple rules with the same specificity, the last rule applies, like CSS and laws but not BML.

Natural (1Y)

(1Y)-(Quasi-)NAT
X!T/O, 7.5− NLTC
1Z8.5–6.0 NLTC, usually 5+#
1NT15–18 HCP, usually BAL 6.5–6.0 NLTC and likely stop
2X7.5–6.0 NLTC, 5+#
2ZPRE, 9.5–8.0 NLTC, usually 6+#
2NT!UNT, PRE or STR, 5+ 5+ in the lowest two unbid suits
3XZPRE, 8.5–8.0 NLTC, usually 7+#
3Y!Gambling, SOL 7+ suit without stopper
3NT!Gambling, SOL 7+ suit with stopper

Cuebids

I advocate using cuebids for 5+ 4+ two suiters, except (1♠)-2♠ that forces playing at the 3-level. The strength shall be either too weak for an opening or too strong for a direct overcall.

  • (1♣)-2♣!: Landy, 5+ 4+ majors or 44(41)
  • (1♦)-2♦!: Flannery, 4+♠, 5+♥
  • (1♥)-2♥!: Muiderberg, 5+♠, 4+m
  • (1♠)-2♠!: Michaels, 5+♥, 5+m

Landy is just Ekren 2♣ but a forcing overcall. I suggest using its continuations. Muiderberg also coincides an opening convention. Michaels is a special case of Muiderberg. The only thing we need to discuss here is Flannery, deprived of the 2♦ relay compared to Landy.

Flannery (1♦)-2♦ is close to Flannery 2♦ and the original Ekren 2♦. I suggest continuations from BTU Ekren + Lebensohl.

(1♦)-2♦-PRE or STR, 5+♥, 4+♠
2NT!LEB
3♣!INV+, 3+♠
3♦!INV+, 3+♥

P-P-(1Y)

By passed hand, overcalls that require opening strength (7.5− NLTC) become one trick weaker. 1NT becomes minor suit oriented takeout.

P-P-(1Y)-(Quasi-)NAT
XT/O, 8.5− NLTC
1NT!T/O, 8.5− NLTC, 4+ 4+ in the lowest two unbid suits
2X8.5− NLTC, 5+#

(1Y)-P

Balancing overcalls tend to be intermediate. Jump overcalls are sound because there is no one to preempt. On the other hand, constructive overcalls are light because partner may have passed a weak notrump.

Unpassed 2NT is no longer unusual because we’ve got more steps on the notrump ladder.

  • 13–15 HCP: 1NT
  • 16–18 HCP: X, then notrump
  • 19–21 HCP: 2NT
(1Y)-P--
XT/O, 8+ HCP
1Z8–15 HCP, 4+#
1NT13–15 HCP with stopper
2X8–15 HCP, 5+#
2Z, 3X11–15 HCP, 6+#
2NT19–21 HCP with stopper

(1Y)-X

The takeout double is one of the oldest conventions. Most players bid naturally to the double. However, I suggest transfer advances at 3Y+. This way, we can separate paths to suit games by strength and by length.

(1Y)-XT/O
1ZNAT NEG, 0–7, usually 4+#
1NTCONST, 8–10
2XNAT NEG, 0–9, usually 4+#
2Y!
RESP.
INV 4= suit with stopper.
FG.
2ZMild INV, 8–12, 4+#
2NTINV, 11–12
3XINV, 10–12, 5+#
3YZ!TRF INV+, 10+, 5+ next suit
3♠!Ask for stopper
(1M)-XT/O
4m!Leaping Michaels, 5+oM, usually 5+#
4M!Leaping Michaels, 5+♦, 5+♣
4oMPRE, usually 7+#
5mPRE, 7+#
(1m)-XT/O
4m!Leaping Michaels, 5+♠, 5+♥
4om!Leaping Michaels, 5+M, usually 5+#
4MPRE, usually 7+#
5omPRE, 7+#

(1Y)-1Z

Whenever there is a debate between forcing and non-forcing responses, choose transfer responses!

—I, Chen-Pang He (jdh8) @BTU, 2024

I sometimes relabel suit variables from the main title.

  • (1X)-1Y
  • (1X)-1Z
  • (1Y)-1Z

I use these formulae interchangeably to accommodate a new-coming strain, e.g.

  • (1X)-1Y-1Z
  • (1X)-1Z-2Y
  • (1Y)-1Z-2X

In competitive bidding, we want more space for raises. On the other hand, notrump already shows length or strength in the adverse suit. The “standard” and naïve approach is to reuse the cuebids for forcing raises. However, there are two reasons to use Rubens advances AKA transfer advances.

There is a debate if new suit advances are forcing or not. For a suit lower than Y (say X), forcing is decent. Aggressor has a cheap cuebid [(1Y)-1Z-2X; 2Y!] to show opening strength, similar to Drury. Nevertheless, when the auction goes (1X)-1Z-2Y, opener has a problem to rebid a minimum opening hand without a stopper:

  • 2Z: utterly an underbid
  • 2NT: lies about the stopper
  • 3Y: an overbid

On the other hand, it is not the most effective to allocate forcing bids at cuebids. When we have a fit, we have little interest in exploring side suits. Space between the forcing raise and Z is unnecessary. Therefore, it is the most useful to let Z − 1 transfer to Z. Consequently, the strains [Y .. Z − 1] map to the suits [Y + 1 .. Z].

Upper strains [Z .. NT]

Upper new suits are always major suits. Only (1m)-1Y-1M is forcing. The other advances are non-forcing because they need little further information.

(1X)-1Y-NAT
1ZF, 4+#, usually 8+
1NTNAT, 9–12
2YCONST, 3+#
2ZPRE, 6+#
2NTNAT INV, 13–15
3YPRE, 4+#
(1m)-1Y-1M-4+#
1NTNAT, –12 HCP
2mLIM+, 3+ SUPP
2XNAT, 9–14, usually 4+#
2YNAT, 12–14, usually 6+#
2ZNAT, 12–17, usually 4+#
2MCONST, 3+#
2NTNAT INV, 13–15 HCP
3mCONST, 4+ SUPP
3XNAT, 15–17, usually 4+#
3YNAT, 15–17, usually 6+#
3MPRE, 4+#

Transfer advances [Y .. Z − 1]

The middle strains are transfer advances for the useful space principle. Z − 1 is home to the forcing raises.

(1X)-1Z-NAT
2XY!TRF, usually 9+ HCP and 5+ cards
2Z − 1!TRF LIM+, 3+ SUPP
3XY!TRF INV+, 6+ cards
3Z − 1!TRF CONST, 4+ SUPP

Lower new suits (X)

Lower new suits are always minor suits. Since minor suit games are hard to make, bidding a new minor suit somehow marks failure to bid a major suit or notrump. Aggressor should be aware that the new minor suit might be a convenient suit to make a forcing advance.

(1Y)-1Z-NAT
2XF unless by PH, 9+ HCP, usually 5+#
3XINV, 6+#
(1Y)-1M-2m-F, usually 5+#
2Y!F, 12–17
2MMIN, 9–11, 5+#
2NNAT INV, 12–14 HCP
3mMIN, 9–11, usually 4+#
3Y!FG, ask for stopper
3MNAT, 15–17, usually 6+#

(1Y)-1NT

I suggest playing Gladiator at (1M)-1NT, which is more effective against a major suit opening, especially 1♠. Aggressor can have 5 hearts at (1♠)-1NT because 2♥ would be an underbid. We get an additional cuebid to invite with 3 hearts, roughly equivalent to Puppet Stayman. There is also an indirect 3NT for choice of games with 3 hearts.

This version of Gladiator originates from a BTU gadget.

(1♠)-1NT

(1♠)-1NT-STR ~BAL
2♣!(R), Gladiator
2♦♥INV, 5+#
2♠!STAY, INV+, 4=♥
2♠-3♠!Choice of games, e.g. MAX 3433
2NT!NF INV, 5+♣
3XFG, 5+#
3♠!SPL, 0–1♠, 4=♥
4♣♦!Leaping Michaels, 5+♥, usually 5+#
4♥S/O, 6+♥
4♠!Leaping Michaels, 5+♦, 5+♣
(1♠)-1NT-2♣-Gladiator
2♦!P/C
2♥!P/C, 5+♦
2♠!MAX, 4=♥, 4+♦
(1♠)-1NT-2♣; 2♦-P/C
PS/O, 5+♦
2♥S/O, 5+♥
2♠!INV, 3=♥
2NTBAL INV
3♣S/O, 6+♣
3♦♥INV, 6+#
3♠!SPL, 0–1♠, 0–3♥
3NT!Choice of games, 3=♥

Slow 3NT still has 3=♥ if RHO bids up to 2NT.

(1♠)-1NT-(2♣♦♥♠)--
2NT!TRF LEB
3♣!TRF INV+, 5+♦
3♦!TRF INV+, 5+♥
3♥!FG STAY, 4=♥
3♠!SPL, 0–1♠, 4=♥
(1♠)-1NT-(2♣♦♥♠)-2NT-TRF LEB
3♣!P/C
3♣-3♠!SPL, 0–1♠, 0–3♥
3♣-3NT!Choice of games, 3=♥
3♦!P/C, 5+♣
3♥!P/C, MAX, 4+♦, 4+♣
(1♠)-1NT-(2NT); (3♠)-P--
XPEN, 3=♥
3NT!Choice of games, 3=♥

I have not yet come up with how we utilize the slow cuebid.

(1♥)-1NT

(1♥)-1NT-STR ~BAL
2♣!(R), Gladiator
2♦♠INV, 5+#
2♥!STAY, INV+, 4=♠
2♥-3♥!Choice of games, e.g. MAX 4333
2NT!NF INV, 5+♣
3XFG, 5+#
3♥!SPL, 0–1♥, 4=♠
4♣♦!Leaping Michaels, 5+♠, usually 5+#
4♥!Leaping Michaels, 5+♦, 5+♣
4♠S/O, 6+♠
(1♥)-1NT-2♣-Gladiator
2♦!P/C
2♥!P/C, 5+♦
2♠!P/C, MAX, 4=♠, 4+♦
(1♥)-1NT-2♣; 2♦-P/C
PS/O, 5+♦
2♠!S/O, 5+♠
2NTBAL INV
3♣S/O, 6+♣
3♦♠INV, 6+#
3♥!SPL, 0–1♥, 0–3♠

(1♣♦)-1NT

Otherwise, I suggest ignoring the minor suit opening. Take the 1NT overcall as a strong notrump opening.

Natural (1NT)

Good, Better, Best recommends using conventional double over a strong notrump. We consider a natural notrump opening strong if at least half of the hands contain 15+ HCP. For instance, 14–16 is considered strong but 13–15 is not.

Over strong notrump

We play Woolsey, Multi-Landy with a conventional double, in all seats.

(1NT)-STR, usually 15+
X!CONST, 5+m, usually 4+M
2♣!UNBAL PRE, 4+♠, 4+♥, usually (54)(xx)
2♦!PRE, 6+M
2♥!PRE, 5+♥, 4+m
2♠!PRE, 5+♠, 4+m
2NT!UNT, 5+♦, 5+♣
(1NT)-X-CONST, 5+m, usually 4+M
2♣!P/C
2♦!Ask for the major suit

The other overcalls already correspond to preemptive openings in this book.

Over weak notrump

We play plain Landy against a weak notrump. This simple defense undermines their systems on approach over (1NT)-2♣. Meanwhile, we still threat to stop in our natural 2♦.

(1NT)-WEAK, usually 12–14
XPEN, 14+
2♣!UNBAL, 4+♠, 4+♥, usually (54)(xx)

By passed hand, we play the defense against a strong notrump.

Natural (2X)

(2Y)-NAT
X!T/O, 12+
2ZNAT, 12–17, 5+#
2NTNAT, 16–18
3XNAT, 14–18, often 6+#
3YAsk for stopper, SOL 7+ suit or STR T/O
3ZNAT, 15–17, 6+#
(2m)-NAT
4m!Leaping Michaels, 5+♠, 5+♥
4om!Leaping Michaels, 5+M, usually 5+#
4NT!NF S/T in om
(2M)-NAT
3M!Ask for stopper, SOL 7+ suit or STR 4+♣ 4+♦
4m!Leaping Michaels, 5+oM, usually 5+#
4M!Leaping Michaels, 5+♦, 5+♣, usually unstopped
4NT!NF UNT with stopper, 5+♦, 5+♣

(2♣)-X

I don’t recommend Rumpelsohl for (2♣)-X. It works better at (2♦♥♠). I have a better yet simple plan: Rubens advances.

(2♣)-X-T/O
2XNAT NF
2NTNAT INV
3♣!INV+ TRF, 5+♦
3♦!INV+ TRF, 5+♥
3♥!INV+ TRF, 5+♠
3♠!FG, usually 6+♦