Incontract bridge and particularly in duplicate bridgeaconvention card is a summary of the conventions and treatments that a particular pair is using.[1] The Laws of Duplicate Bridge specify that "Each partnership has a duty to make available its partnership understandings to opponents before commencing play against them."[2]
In games regulated by the American Contract Bridge League (ACBL), this is generally done using a form with a standard format.[3] The ACBL General Conditions of Contest specify that "Each member of a partnership must have a completely filled out convention card available for the opponents."[4] Convention card formats may vary by jurisdiction. There are also various computer programs which a player may use to create and print a convention card.
In tournament bridge, the opponents' convention cards are supposed to be marked telling you what their ranges are on the most common notrump sequences.
