The Gerber convention is a 4 response to a no-trumps bid. Like Blackwood, it is a slam investigation bid that asks partner how many aces he holds. The difference from Blackwood is that Gerber is only used for no-trumps. This is because 1NT-4NT is natural, inviting partner to bid 6NT.
Responses to 4
- 4 Shows 0 or 4 aces.
- 4 Shows 1 ace.
- 4 Shows 2 aces.
- 4NT Shows 3 aces.
Responses to 5
- 5 Shows 0 or 4 kings.
- 5 Shows 1 king.
- 5 Shows 2 kings.
- 5NT Shows 3 kings.
- A direct 4 response to any no-trumps bid (or overcall) is Gerber.
- A jump rebid of 4 in response to a natural no-trump bid is Gerber.
Adding partner's 15-17 HCP to his own 17 HCP, responder knows that his side has 32-34 HCP. A small slam in no-trumps is possible, but the Gerber
Responder is interested in 6 but doesn't want to bid it missing 2 aces. If partner shows all 4 aces, responder can bid
Responder is interested in a club slam.
2 Shows 4 hearts.
Gerber can also be used as a jump rebid after a Stayman sequence. Here, responder is interested in
If a trump suit hasn't been identified yet, then 4 is Gerber after any natural no-trumps rebid.
2 Denies a 4-card major.
4 is NOT Gerber. It is natural because it was not a jump.
- Gerber requires a lot partnership discussion. It can get misidentified as a splinter bid (showing a club singleton/void), or as club support if partner bid clubs earlier.
- Gerber should not be used with a void.