The purpose of the convention is to make sure the partnership can locate a 4-4 Major suit fit after one partner opens 1NT. We assume the 1NT opener will not have a 5-card Major suit.
Assuming a 15-17 point 1NT opening, Responder will usually not reply with fewer than 9 points since game would not be likely. If the Responder has one or more 4-card Majors the response is an artificial 2♣, which requests the 1NT Opener to show a 4-card Major if he has one.
- The 1NT Opener replies as follows:
- With 4 ♥s : bid 2♥.
- With 4 ♠ : bid 2♠
- With 4 ♥s and 4 ♠ : bid 2♥.
- With no 4-card Major : bid 2♦
After a 2NT opening bid, (20-21 points) 3♣ is Stayman with the Opener's rebids one level higher.
Stayman is an almost essential convention and many pairs use it as one of their few artificial conventions. However, it is even more powerful when used in conjunction with the Jacoby Transfer convention.
Lesson available.