Play bridge with Wbridge5!

Departures from the Standard French System

The bidding system used by the program, while implementing the principle of 5-card majors, offers some simplifications to conform to the standard French system.

If the SEF option is invoked:

• Responder's cue bid with an unpassed hand shows a strong hand with more than 16 total points, but not necessarily a fit


• The bid of 4NT is always Blackwood, except in the following cases:
  • An overcall of 4NT shows a hand with two suits of at least five cards each. The suits are the lowest ranking suits unbid by the opponents
  • After an opening 1NT or 2NT, 4NT is invitational


• No fourth-suit forcing, except for bids of 2 ♣ and 2 ♦. In particular, the bid of 1 ♠ in the sequence 1 ♣ - 1 ♦  - 1 ♥ - 1 ♠ is natural (4 cards)


• No third-suit forcing


• After an opening 1 ♣ which is neither raised or rebid, the bid of 2 ♣ by an opponent is always natural except in the protective position, where the sequence 1 ♣ - - 2 ♣ shows a hand with two 5-card majors

Without the SEF option:

The following additional differences will be found:

• With more than 16 total points, responder jumps in another suit, with or without a fit, unless the pair are using the Bergen convention. In this case the responses of 2 ♣ and 2 ♦ are unlimited. Otherwise, a non-jump response at the 2-level shows 12 to 16 total points. A response at the 1-level shows a maximum of 16 total points


• The 1NT opening may be made with a 5-card major if the distribution is 5332, and the option is checked


• A bid of 2NT in the protective position has the same meaning as a suit overcall


• In the sequence 1 minor - 1 major - 3NT, opener's 3NT rebid shows a balanced hand with 18 to 19 honour points and a 6-card minor suit