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
Contract bridge a few years contract bridge had so supplanted other forms of the game that "bridge" became synonymous with "contract bridge". In the US and many other countries, most of the bridge played today is duplicate bridge, which is played at clubs, in tournaments and online. The number of people playing contract bridge has declined since its peak in the 1940s, when a survey found it was played in 44% of US households. The game is still widely played, especially amongst retirees, and in 2005 the ACBL estimated there were 25 million players in the US. Bridge is a game of