Strong 1NT opening

Strength: 15-17 HCP


1N - ?

Overview of the approach with different hand types

Further bidding after Stayman

1N - 2
any - ?

1N - 2 responder has a 4+ major
2 - ? opener has no 4-card major

1N - 2
2 - ? 4+ (may have 4-card )

1N - 2
2 - ? 4+ (no 4-card )

1N - 2
2M - 3m Responder: 5+ m, has a 4-card major, GF+
Responder's possible hand types in this 3m bid: Opener's bids:

Further bidding after major transfers

Opener normally bids the responder's suit, all other bids show 4-card support (on 2 at most 2 can be bid because of the CONFI), on 2 a doubleton , 2N, or 3 (minimal hand) can be bid. After Opener completed the transfer, responder's second bids are also transfers, her jump shifts are splinters with 6-card trumps and slam try. 3N shows exactly 4-carder suit, while 3M (raise) shows 5M-332 or similar GF hand offering a choice between 3N and 4M. The second transfer is at least game try and 5-4 or better shape, (5-5 with both majors. Raising your own suit to 4 shows mild slam try with 6+ cards without a shortness, because if you had intended to play your suit on a game level then you had transferred it on on level 4 immediately. Responder second bids are:

1N - 2M-1 (a) 5+ major, (b) 4-card major in a balanced gameforcing hand (c) in 2: CONFI (balanced slam try)
2M - ?

You may notice that with a 5-card major and game try you won't have a good bid without a second suit, thus you should not transfer with these hands at all. (beware, this may be missed when bidding the first transfer - playing second transfers you should think a bid ahead, and bid Stayman with those hands (and your major later).

Opener's reaction to second transfers: suppose, that responder has a game try 5-5:

After minor-suit transfers:

Responder's second bids:

5431 convention

1N-3M shows 2-suiter (54+) with both minors and shortness in the bid suit. May have 5521 or 5530 too. (if you don't have a separate bid for 55 minors, we don't)

Opener' bids:

On intervention

If our 1N is doubled:

DONT style escape as after mini NT

On doubles that does not promise strength (e.g. DONT): system on, RDBL is at least gam try, seeks a penalty and forcing to 2 (takeout doubles over 2)

When our Stayman is doubled:

1N (p) 2 (X)
?   (Opener passes with srength or length, trsnfers to the usual reponse without that)