Acol

Acol is the bridge bidding system that, according to The Official Encyclopedia of Bridge, is "standard in British tournament play and widely used in other parts of the world". It is basically a natural system using four-card majors and, most commonly, a weak no trump.

It is named after the Acol Bridge Club, previously located on Acol Road in London NW6, where the system started to evolve in the early 1930s. According to Terence Reese, its main devisers were Maurice Harrison-Gray, Jack Marx and S. J. "Skid" Simon. Marx himself, writing in the Contract Bridge Journal in December, 1952, said: "...the Acol system was pieced together by Skid Simon and myself the best part of 20 years ago." In another account, Marx and Simon...

progressively, infected and re-infected each other with the virus of the game. In interminable slow walks...they would wander round and round the quiet streets, endlessly discussing the refinments of the enthralling game. Out of these conversations—surely a strange gestation—was born Acol as we know it and play it to-day.

The first book on the system was written by Ben Cohen and Terence Reese. Skid Simon explained the principles that lay behind the system, and the system was further popularised in Britain by Iain Macleod. The Acol system is continually evolving but the underlying principle is to keep the bidding as natural as possible. It is common in the British Commonwealth but rarely played in North America.

As a bidding system, Acol has the following characteristics:

Acol is an unregulated system. There is no Acol governing body and no single publication containing the "official" Acol (unlike, for example, Standard American Yellow Card). It can be compared to a living language since it is liable to change at the whim of users. The main versions of Acol in use today are:

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