Contract bridge awards a bonus for holding a certain combination of high cards), although some are common between the two. A larger bonus is awarded if the declaring side makes a small slam or grand slam, a contract of 12 or 13 tricks respectively. If the declaring side is not vulnerable, a small slam gets 500 points, and a grand slam 1000 points. If the declaring side is vulnerable, a small slam is 750 points and a grand slam is 1,500. In rubber bridge, the rubber finishes when a partnership has won two games, but the partnership receiving the most "overall" points
Contract bridge (a union of the ABL and the USBA), and it remains the sanctioning body for bridge tournaments in North America. In 1958, the World Bridge Federation (WBF) was founded to promote bridge worldwide, coordinate periodic revision to the Laws (each ten years, next in 2017) and conduct world championships. In tournaments, "bidding boxes" are frequently used, as noted above. These avoid the possibility of players at other tables hearing any spoken bids. The bidding cards are laid out in sequence as the auction progresses. Although it is not a formal rule, many clubs adopt a protocol that the bidding cards