Gerber is a contract bridge convention devised by William Konigsberger and Win Nye from Switzerland who published it in 1936; John Gerber of Texas introduced it to North America in 1938 where it was named after him. It is similar to Blackwood but uses 4 instead of 4NT as a relay (asking) bid to inquire about the number of aces held by partner. A further relay bid may follow to inquire about the number of kings held. Gerber is used primarily after notrump openings, responses, and rebids, making it a complement to Blackwood rather than a replacement. Some club players also use it after suit bidding, but most experts do not recommend this. Purpose Because bidding and making a slam or grand slam contract in bridge gains significant bonus scoring points, partnerships will strive to bid them whenever their combined card assets are deemed sufficient. Knowing the number of aces and kings jointly held is usually crucial to this decision and Gerber is one of several bridge conventions used to ascertain the necessary information. Responses and continuations The ace-asking bid is 4. The criteria for its application vary amongst users and alternatives are detailed below; likewise, a number of response schemes have been developed over the years. Partnership agreement is required on both matters. Original response scheme The original responses to the 4 asking bid are: 4 = 0 aces 4 = 1 ace 4 = 2 aces 4NT = 3 aces 5 = 4 aces Modern response schemes Most modern bridge literature recommend the following response scheme: 4 = 0 or 4 aces 4 = 1 ace 4 = 2 aces 4NT = 3 aces However, some experts favour the following responses, analogous to Roman Blackwood: 4 = 0 or 3 aces 4 = 1 or 4 aces 4 = 2 aces Other response structures have been devised along similar lines and partnership agreement is required to establish a preferred scheme. Continuations Like Blackwood, a follow-on bid may be used in Gerber to ask for kings. There are two principal approaches for the king-ask bid: Bid 5 to ask for kings or Use the next available bid, skipping the trump suit if one has been agreed, to ask for kings. Step-responses mirror those for the ace-ask bid. Application Comparison with Blackwood The main perceived advantage of Gerber is that it is bid at a lower level and therefore allows