Drury convention

The Drury convention is a bridge convention, used to show a game-invitational major suit raise by a passed hand while guarding against a light opening by partner in third or fourth seat. It is initiated by an artificial and forcing 2♣ response by the passed hand to a 1♥ or 1♠ opening by partner. The 2♣ bid shows at least 3-card support for opener's suit with 10-12 support points and asks opener to clarify the strength of his opening hand. The convention is also known in Europe as "Toronto".

The convention was developed by Canadian Douglas Drury (1914-1967) and his then playing partner Eric Murray (b1928) to manage Murray's propensity to open light in third seat. Opening light (i.e. with marginally less than normal values) in the third seat is a common and effective bidding tactic because the player in the fourth seat may well have the best hand at the table and be poised to open the bidding given the opportunity. A third seat light opening, especially in a major suit, will act preemptively to make it harder for that player to enter the bidding. However, this creates two problems:

The traditional method for showing good support for opener's suit is to jump to the 3-level (e.g., 1♥ - 3♥). On those occasions when partner has opened light, this may result in an overly ambitious contract, despite the good support. Drury allows responding partner to learn if his opening partner has opened with a normal opening hand or has a light opening hand. If it is a light hand, or even a minimal normal opening hand, the contract can be set at the 2-level, whereas non-Drury partnerships, with the same hands, would have to sign-off at greater risk at the 3-level. Owing to its role in the competitive bidding of part-score contracts, Drury is advantageous primarily in match point scoring events.

The convention was first published in The Bridge World in January 1957. Murray's presentation of the original convention included the following features:

A rebid of 2♦ shows a full opening. While not universally accepted, a bid of 2♥ by opener after opening 1♠ is also a weakish bid showing 5 spades and 4 hearts (or better). With a good hand (say 15 or more points) opener may simply jump to game (4 of the major suit). Other bids tend to be natural and descriptive, in effect a game try. With an excellent hand, opener may be interested in a slam and will bid accordingly.

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