Grand slam force Grand slam force The Grand Slam Force is a bidding convention in contract bridge that was developed by Ely Culbertson in 1936. It is intended to be used in cases where the combined hands of a partnership are so strong that a slam (winning at least 12 tricks) is a near-certainty and a grand slam (winning all 13 tricks) is a possibility. It allows one partner to gain information on the quality of trumps in the other partner's hand. When this convention is in force, a bid of 5NT (five notrump), when it does not conflict with other conventions used
Bidding (cards) Bidding (cards) Bidding is the process in many card games, such as Skat, Pinochle, Binokel, Bridge, Solo Whist, Préférence, L’Hombre, Bauernschnapsen and most types of Tarock, whereby players vie to be able to specify the type of contract, the trump cards and/or to be able to pick up a set of face-down cards known variously, for example, as the talon, skat, dabb. Players may raise the bid (by bidding a higher contract or point value) until the highest bidder is determined when the others all say "pass". Bidding may be done in successive pairs as in Skat (in the sequence: