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
Bridge scoring essential to understanding bridge scoring: Bridge scoring consists of nine elements. Not all elements are included in all game variants and the method of accumulation of the elements over several deals varies. If the contract is made, the score for each such deal consists of: If the contract is defeated, the defenders receive In rubber bridge only, In duplicate bridge only, Contract points are awarded for each odd trick bid and made. Their values depend on the suit (or notrump) and whether the contract is doubled or redoubled; they are not affected by vulnerability. Tricks won beyond that necessary to