A convention is an artificial bid or series of bids carrying a meaning other than the apparent natural one.
4.1 The Stayman Convention
After an opening bid of 1NT a bid of 2C is asking opener to show any 4 card Major suits with a view to finding a fit in one of the Majors.
Before using Stayman always consider the need to make a sensible re-bid (or a pass) if opener has no 4 card Major. With a balanced hand you need to have at least 11 points because you may have to revert to 2NT if no fit is found. With longer Major suits, Stayman can be used with a very weak point count with a view to signing off in 2 of a Major.
Opener’s responses to 2C are:
- 2D with no 4 card Major
- 2H with 4 hearts (& possibly 4 spades as well)
- 2S with 4 spades (but not 4 hearts)
With a weak hand responder’s re-bid options are:
- Pass if a fit has been found
- Sign off in 2 of his best Major suit
- Sign off in 3C if he has a genuine club suit
With a stronger hand responder’s re-bid options are:
- If a fit has been found, raise invitationally to the 3 level or bid game
- If a fit has not been found, bid a Major invitationally at the 3 level or bid game
- Bid NT’s using the same point ranges as for a direct raise after a 1NT opening bid (2NT with 11 -12 pts, 3NT with 13 – 15 pts).
Note: after an opening bid of 2NT, a bid of 3 Clubs is Stayman with similar responses at the 3 level.
4.2 The Blackwood Convention
Except after a direct raise from 1NT or 2NT, a bid of 4NT is asking partner how many Aces they hold with a view to playing in a slam. Responses are:
- 5C with 0 or 4 Aces
- 5D with 1 Ace
- 5H with 2 Aces
- 5S with 3 Aces
A subsequent bid of 5NT is asking partner how many Kings are held. Responses are:
- 6C with 0 or 4 Kings
- 6D with 1 King
- 6H with 2 Kings
- 6S with 3 Kings
4.3 The Gerber Convention
After an opening bid of 1NT or 2NT, a bid of 4NT is quantitative and cannot be used as the Blackwood convention (asking for Aces - see 4.2).
After a 1NT or 2NT opening bid, a bid of 4C asks partner how many Aces they hold with a view to playing in a slam. Responses are:
- 4D with 0 or 4 Aces
- 4H with 1 Ace
- 4S with 2 Aces
- 4NT with 3 Aces
A subsequent bid of 5C is asking partner how many Kings are held. Responses are:
- 5D with 0 or 4 Kings
- 5H with 1 King
- 5S with 2 Kings
- 5NT with 3 Kings