Double Club System

Auctions starting Pass, 1H/S, 2C, 2D

What has been shown?

Opener has shown a balanced hand with 11-13 hcp.

Responder has shown either (a) a balanced hand of 12-13 hcp, which may or may not have support for opener's suit, or (b) a slightly weaker hand with 4-card support for opener's suit and 7 losers.

Strategy

Responder will always have game-invitational values after this bidding. He bids opener's suit unless he has only a doubleton in support, after which opener passes if minimum or continues if maximum. With only a doubleton in opener's suit, the contract will be 2NT or 3NT and responder has two ways of inviting, depending on whther he himself is minimum or maximum.

Continuations

2/
Game-invitational, showing 3-card or 4-card support. Responder has 7 losers (and may have less than 12 hcp with 4-card support). Opener should pass with 8 losers but accept the invitation with 7 losers. Opener's bid to accept the invitation should be 3NT, so that responder can pass with 3-card support only or correct to 4H/S with 4-card support.
2 (after a 1 opening bid)
2 (after a 1 opening bid)
Artificial and weakly game-invitational in no trump. (Note that the bid of the other major cannot be natural since there cannot be a fit in this suit on this bidding, because opener would start with 1H if holding both majors and responder would bid 1S if having spades.) Responder has only doubleton support for opener's major and has 12 hcp. Opener should refuse the invitation (with 2NT) unless having a maximum 13 hcp.
2NT
Natural and strongly game-invitational in no trump. Responder has only doubleton support for opener's major and has 13 hcp. Opener should accept the invitation with most hands of 12+ hcp.

No other bids are allowed.

Author: Chris Burton
Gravesend Bridge Club