Natural 1♣♦

The minor openings are the most frequent openings. Particularly, 1♣ is the most frequent, 1♦ the second. Therefore, it is important to learn the continuation of these openings.

The minor openings can be made from three kinds of hands:

• Open the longer minor in a balanced hand with 12–14 or 18–19 HCP without a 5-card major.
• Open the longest suit in an unbalanced hand with normal openings strength.
• Open the longest suit in a 3-suiter or 5-4-3-1 with 2♣ strength where the 5-card suit is a minor. See also the dedicated section.

Opener probably has a 4-card major. Therefore, responder bids a major first whenever it can. A notrump or a support in minor always denies a biddable major.

Responses to 1♣

The 1NT response is always constructive because there is no suit below clubs. When 1NT acts as a dustbin, responder bids 1NT to show a suit below the opening. This is obviously not the case for 1♣.

Choice of new suit

1. Choose the longest suit.
2. To break a tie, bid the cheapest call for 4-4, the highest suit for 5-5 or above.
3. Nevertheless, if responder cannot virtually 2/1 (< 12 points) but has normal responding strength (5+ HCP) and a biddable major, skip diamonds unless 6+ cards or at least AJxxx or KQJxx.

The partnership can usually make 2 of a suit and sometimes 1NT with normal responding strength. Bypassing diamonds slightly preempts in a partscore dog fight. However, when responding with void clubs and insufficient strength, responder bids 1♦ to seek 1♠/♥.

• ♠K965 ♥65 ♦KJ863 ♣98: Bid 1♠. Skip diamonds because you cannot force to game.
• ♠10983 ♥9 ♦KQJ103 ♣J72: Bid 1♦. These diamonds are eligible.
• ♠KQ93 ♥72 ♦AK73 ♣J63: Bid 1♦ because you can force to game.
• ♠KQ105 ♥7643 ♦J642 ♣10: Bid 1♥. Skip diamonds, and then 1♥ is the cheaper call.
• ♠Q974 ♥A1062 ♦AQ108 ♣7: Bid 1♦. No skipping for a game-forcing hand.

Simple raise

The 2♣ simple raise is not so simple.

For preemption, responder raises to 2♣ with 4+ clubs and no 4-card major in a non-constructive hand. This is the only case where 2♣ shows only 4 clubs.

For a constructive hand, responder jumps to 3♣ with 5+ clubs, but a balanced 7–9 HCP hand prefers constructive 1NT. Probing Wbridge5 5.12 shows no limit raise in clubs: stronger hands bid 1♦, 2NT, 3NT, or a splinter.

• ♠976 ♥965 ♦A109 ♣J1085: Bid 2♣. This hand is too weak for constructive 1NT.
• ♠QJ6 ♥J5 ♦J932 ♣J987: Bid 1♦. This hand is too weak for constructive 1NT.
• ♠964 ♥104 ♦AJ65 ♣A1094: Bid 1NT. The constructive 1NT is preferred over a minor suit.
• ♠53 ♥K84 ♦432 ♣KQ765: Bid 1NT. The constructive 1NT is preferred over a minor suit.
• ♠A75 ♥7 ♦874 ♣QJ6532: Bid 3♣. Make a constructive raise with unbalanced distribution.

Adjusted responses by a passed responder

Since responder has made a limit pass, which denies strength of opening, new-suit responses are no longer forcing.

Jump shifts from 2♥ on are fit-showing because responder gave up preemptive opening.

Responses to 1♦

Choice of new suit

1. Choose the longest suit.
2. To break a tie, bid the cheapest call for 4-4, the highest suit for 5-5 or above.

Adjusted responses by a passed responder

Not probed

• P - 1♣ - 2♦ and 2♥, and P - 1♦ - 3♣: no board.
• Responses above 21 HCP, except 3=3=3=4 hands with 22 HCP.