In the card game contract bridge, DONT is a conventional overcall used to interfere with an opponent's one notrump (1NT) opening bid. DONT, an acronym for Disturb Opponents' Notrump, was designed by Marty Bergen, and is therefore also referred to as "Bergen over Notrump". Although the method is often criticized for being too nebulous, it remains fairly popular. The convention was first published in the September/October 1989 issue of Bridge Today.
In DONT, the two-level overcalls of trump show a two suiter [lower-alpha 1] of the suit bid and an unspecified higher-ranking suit. The feature distinguishing DONT from other similar conventions such as Cappelletti is the use of the double to show length in one suit, rather than hand strength or for penalty. [2] DONT is played mainly for interference rather than to establish a contract, so it may occasionally be used for low-strength hands. [1] : 56
DONT can be used with low hand strength, but intervenor must have good suits when vulnerable. [3] DONT features the following calls: [1] : 56
Preferences vary as to the use of the 2♠ bid. Some treat it as weaker than the sequence of a double followed by 2♠; others play it as showing a solid (runable) spade suit; other treatments are possible and partnership discussion and agreement is necessary.
DONT is normally applied as a defense to strong notrump opening bids, but some people have created various modifications to DONT to apply them to weaker notrump openings. The difference is that the bidder shows opening-bid values and the partner of the doubler may pass to convert the single-suited hand into a penalty double.
Against the mini-notrump opening bid which shows 10-12/13 HCP (also known as the Kamikaze 1NT):
There are variations in the agreed responses, and partners should establish a clear agreement.
One common system of responses is:
When the opponents play Precision Club or other strong club system, 1♣ usually describes a 17-19 point hand. Accordingly, DONT can also be employed over these types of systems.
A variation of the system, claimed to provide additional disturbance of the notrump auction, calls for the partner of the intervenor to bid his cheapest doubleton when the intervenor has shown a single-suited hand. This relies on the Law of total tricks to find adequate protection at the three level.
| West | North | East | South |
|---|---|---|---|
| 1♣ | 2♣ | Dbl | 2♥ |
| Dbl | 3♣ | ? |
In this auction West has a strong hand (17+ points) and East has shown a positive response (8+ points) so they must be in the game zone. West's double of 2♥ is not clear. It might mean that he has a heart suit, but how long of a suit is it? South is known to have at most two cards in that suit. North and South meanwhile have found a minimum 9-card club fit (North with 6 and South with 3+ clubs). In an auction like this, East may just have to bid 3NT and hope for the best. The variation does have a few risks, for example if the partner of the intervenor has two short suits the fit in the agreed suit may be deficient.
Stayman is a bidding convention in the card game contract bridge. It is used by a partnership to find a 4-4 or 5-3 trump fit in a major suit after making a one notrump (1NT) opening bid and it has been adapted for use after a 2NT opening, a 1NT overcall, and many other natural notrump bids.
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 a natural system using four-card majors and, most commonly, a weak no trump.
Polish Club is a bridge bidding system which was developed in Poland, where it is the most popular bidding system, and which is also used by players of other countries. It is a type of small club system.
The forcing notrump is a bidding convention in the card game of bridge.
The Jacoby transfer, or simply transfers, in the card game contract bridge, is a convention in most bridge bidding systems initiated by responder following partner's notrump opening bid that forces opener to rebid in the suit ranked just above that bid by responder. For example, a response in diamonds forces a rebid in hearts and a response in hearts forces a rebid in spades. Transfers are used to show a long suit, usually a major, and to ensure that opener declare the hand if the final contract is in the suit transferred to, preventing the opponents from seeing the cards of the stronger hand.
The Michaels cuebid is a conventional bid used in the card game contract bridge. First devised by Michael Michaels of Miami Beach, FL, it is an overcaller's cuebid in opponent's opening suit and is normally used to show a two-suited hand with at least five cards in each suit and eight or more points.
These terms are used in contract bridge, using duplicate or rubber scoring. Some of them are also used in whist, bid whist, the obsolete game auction bridge, and other trick-taking games. This glossary supplements the Glossary of card game terms.
In the card game contract bridge, a takeout double is a low-level conventional call of "Double" over an opponent's bid as a request for partner to bid his best of the unbid suits. The most common takeout double is after an opponent's opening bid of one of a suit where the double shows a hand with opening values, support for all three unbid suits and shortness in the suit doubled. Normally, the partner of the doubler must bid his best suit but may pass if (a) his right hand opponent intervenes or (b) on the more rare occasions when his hand is such that he wishes to convert the takeout double to a penalty double.
Cappelletti is one of many defensive bridge bidding conventions used in the card game contract bridge to compete or interfere in the auction when an opponent has opened one notrump (1NT). Usually attributed to Michael Cappelletti and his longtime partner Edwin Lewis, origin of the concept is also claimed by Fred Hamilton, John Pottage and Gerald Helms. Cappelletti can show a variety of one- and two-suited hands while retaining the penalty double for stronger hands.
Landy, named after its inventor Alvin Landy, is the first of several conventional defenses created to compete against an opponent's one notrump (1NT) opening. Landy is a 2♣ overcall of the opponents' 1NT opening to show at least four cards in each of the major suits; all other bids are natural. Requirements for the overcall vary from partnership to partnership: some require 5-5, some 5-4, and yet others only 4-4. The partner can take a preference to either major or make a non-forcing bid of a suit; 2NT is used as a forcing query.
In contract bridge, a cue bid is either a bid of the opponents' suit, or "slam seeking": a slam-investigating bid made during an auction's later rounds that shows control of a suit.
In contract bridge, an overcall is a bid made after an opening bid has been made by an opponent; the term refers only to the first such bid. A direct overcall is such a bid made by the player seated immediately to the left of the opener, i.e. next in the bidding rotation; an overcall in the 'last seat', i.e. by the player to the right of opener, which is made after two intervening passes, is referred to as a balancing or protective overcall.
Fourth suit forcing is a contract bridge convention that allows responder to create, at his second turn to bid, a forcing auction. A bid by responder in the fourth suit, the only remaining unbid suit, is artificial indicating that responder has no appropriate alternate bid, remains interested in the potential for a game contract and asks opener to bid again to show additional features.
EHAA is a highly natural bidding system in contract bridge characterized by four-card majors, sound opening bids, undisciplined weak two-bids in all four suits and a mini notrump, usually of 10–12 high card points.
Devised by Kit Woolsey, the convention is a defense against an opponent's one notrump opening; especially used at matchpoints. Initial bids are as follows:
New Minor Forcing (NMF), is a contract bridge bidding convention used to find a 5-3 or 4-4 major suit fit after a specific sequence of bids in which opener has rebid one notrump. The convention is triggered by responder at his second turn by an artificial bid of two in an unbid minor; it requires that he hold five cards in the major he has previously bid and an unlimited hand ranging in value from at least game invitational strength to that sufficient to have interest in slam; he may also hold four cards in the other major. Accordingly, there are six bidding sequences in which the New Minor Forcing bid may be applied:
Transfer Walsh is a bidding convention used in contract bridge. After a 1♣ opening bid, responses of 1♦ and 1♥ show heart and spade suits respectively. The "Walsh" terminology refers to the fact that these bids may conceal an equal or longer diamond suit. It allows opener to play a greater proportion of major-suit and no-trump contracts, particularly when using five-card majors.
Unusual vs. unusual is a competitive bidding convention used in contract bridge by the opening side after an opponent has made an overcall showing two suits.
Astro is a contract bridge bidding convention used to intervene over an opponent's one notrump (1NT) opening bid. The name is derived from the initials of the surnames of its inventors - Paul Allinger, Roger Stern and Lawrence Rosler.
XYZ is a bidding convention in contract bridge.