In the card game of bridge, the unusual notrump is a conventional showing a two-suited hand. It was originally devised by Al Roth in 1948 with Tobias Stone, 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. History In his seminal 1953 book, The Roth-Stone System, Alvin Roth suggested that poor matchpoint scores usually result when the opponents are permitted to play low-level contracts and recommended protective bidding tactics for the player in the pass-out (balancing) seat in such auctions. He advocated use of weak jump overcalls and responses at a time when the standard practice was for jump overcalls and responses to show strong hands. In one such application - when the opponents reach the two-level having bid only a major – he recommended an overcall of 2NT, as an artificial protective bid indicating, a probable 9 (or more) points. strong minor suit holding – 5-4, 5-5 or better – and a request for partner to choose between the minor suits. If necessary, responder must bid a three-card minor suit. a warning against bidding the unbid major (however, the unbid major may be bid if self-sufficient). Current usage When an opponent opens the bidding with 1 or 1, the immediate overcall of 2NT shows at least 5-5 in the minor suits (that is, at least five clubs and at least five diamonds). If the right hand opponent (RHO) of the partner of the 2NT bid passes, that partner is expected to bid the minor suit that he prefers at the three-level. The unusual notrump applies the principle that when the natural meaning of a bid is not generally very useful, it is profitable to agree that it means something somewhat opposite. That is, while natural notrump bids show a strong hand with balanced distribution, the unusual notrump shows a weak hand with very unbalanced distribution. If the 2NT bidder bids again freely, then it