Contract bridge grand slam exists. The modern game of contract bridge was the result of innovations to the scoring of auction bridge by Harold Stirling Vanderbilt and others. The most significant change was that only the tricks contracted for were scored below the line toward game or a slam bonus, a change that resulted in bidding becoming much more challenging and interesting. Also new was the concept of "vulnerability", making sacrifices to protect the lead in a rubber more expensive. The various scores were adjusted to produce a more balanced and interesting game. Vanderbilt set out his rules in 1925, and within
Bidding box Bidding box A bidding box is a device used for bidding in bridge, usually in duplicate bridge competitions. Made in various configurations and sizes, it is typically a plastic box with two holding slots, each containing a set of bidding cards: one with 35 cards with symbols of bids, and the other with cards for other calls (pass, double, etc.). Invented in Sweden in 1962, they were first used at a World Bridge Championships game in 1970. Their usage eventually spread in Europe, United States and across the world, and today they present a virtually indispensable piece of equipment even