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
The Bridge World the magazine has periodically polled experts on various bidding treatments and conventions in order to develop a unified system of bidding known as Bridge World Standard. There have been five versions of the system with the latest revision being the 2017 edition. Bridge World Standard has evolved with the practices of North American experts and, similar to the Standard American Yellow Card system promulgated by the American Contract Bridge League, is offered as a system "for use by impromptu or casual partnerships, and as a basis for discussion by those who wish to formulate their own system." The Bridge World