Fourth Suit Forcing
Introduced by Norman Squire. Rebid of the unbid fourth suit by responder shows that the first major suit is a 5 cards suit, besides intention to play NoTrump with minimum of 10-11 High Card Points and asks whether the partner has stopper on that suit. Application on the second level is one round forcing but if it is on the third level it is a game forcing. The opener shows his 3 cards support to responder's first major suit in second or third level according to the high card points he has. Otherwise, bids 2 NT with minimum openning values and 3 NT with more values if he has stopper on the fourth suit. If he does not have support and any stopper on the fourth suit he has to be more creative. In the following auction;
- Opener Responder
- 1 Club 1 Heart
- 1 Spade 2 Diamonds
2 Diamonds is Fourth Suit Forcing, and shows 11+ HCPs and 5 cards of Hearts. Openner shows his support if he has 3 cards of Hearts. Otherwise bid NT with a stopper on Diamonds.
Rebid of 1 spade as the fourth suit is natural and shows 4 cards of Spades. Any jump suit could not be Fourth Suit Forcing even if it is the fourth suit. This kind of jump fourth suit shows at least 5-5 distribution and game values. Another condition for Fourth Suit Forcing is that the other three suits should be called by the partnership. So if one of the suits is called by the opponents then there is no Fourth Suit Forcing.