XY No Trump Convention

The XY no trump convention is a convention in bridge.

Using the convention

After opener's one of a suit (X), partner's one of a suit response (Y) and opener's 1NT rebid (a very common sequence), 2Clubs from opener's partner forces 2Diams from opener. Holding a weak hand with diamonds, one can now pass. Other bids are invitational, describing also the nature of the hand. A 2Diams response to 1NT, however, is game forcing with any hand.

Examples of use

For example, on the sequence 1Clubs-1Spades (with our without opponent's interferring);1NT-2Clubs;2Diams,2Hearts will show an invitational hand with minimum five spades and four hearts, 2Spades an invitational hand with minimum five spades (in which case one does not have four hearts) or possibly six spades with or without four hearts. 2NT will show a balanced invitational hand, 3Clubs typically an unbalanced invitational hand with club support. However, when one instead forces game with 2Diams, opener will immediately start describing his own hand. He may, on basis of the aforementioned auction, with 2Diams being the only difference, bid 2Hearts holding four hearts, 2Spades holding three card spade support, etc. Further bids are primarily natural.

Advantages using XY no trump

XY No Trump gives very good control finding both games and slams, as the final "mission" of the sequence is established at a relatively early stage of bidding.

Playing, as very common in combination with XY no trump, the Walsh convention or even Transfer Walsh, one still has the chance of stopping in 2Diams on weak hands, often impossible using for example Checkback Stayman.

Variations

A popular expanded version of XY no trump is the so-called "XYZ" [http://bridgehands.com/X/XYZ_Convention.htm] , meaning the principles of regular XY no trump is valid even after a one of a suit (X) - one of a suit (Y); one of a suit (or no trump) (Z) auction. It replaces such a method as Fourth suit forcing.

Notes

* [http://bridgehands.com/X/XYZ_Convention.htm A publication on the XYZ variation of the XY no trump Convention]
* [http://org.ntnu.no/mareritt/boasys04.pdf A system publicaton based on Baard Olav Aasan methods, concerning particularly Transfer Walsh and XY no trump (in Norwegian)]

See also

* Walsh convention
* Transfer Walsh
* Checkback Stayman