Unusual notrump

Main articles: Contract bridge, Bidding system, Bridge convention, and Glossary of contract bridge terms

In the card game of bridge, the unusual notrump[1] is a conventional overcall showing a two-suited hand. It was originally devised by Al Roth in 1948 with Tobias Stone,[2] to show the minor suits after the opponents opened in a major.

The convention concept is now generally extended to show the "two lowest unbid" suits. Thus, over 1♣, 2NT shows diamonds and hearts; and over 1♦, it shows clubs and hearts. In addition to succinctly describing the hand to the partner, it deprives the opponents of bidding space, i.e. it has a preemptive effect. A drawback is that it provides the opponents with information about the strength and distribution of the overcaller's hand, potentially enabling improved declarer play should they secure the contract.

  1. ^ Kearse, Amalya (1990). Bridge Conventions Complete (Revised and Expanded ed.). Louisville, KY: Devyn Press Inc. pp. 423, 427, 430. ISBN 0-910791-76-7.
  2. ^ Manley, Brent; Horton, Mark; Greenberg-Yarbro, Tracey; Rigal, Barry, eds. (2011). The Official Encyclopedia of Bridge (7th ed.). Horn Lake, MS: American Contract Bridge League. p. 334. ISBN 978-0-939460-99-1.