Strong notrump openings
The strong notrump openings 1NT and 2NT move some strong balanced hands out of suit openings, clarifying the range of opener. This is crucial in finding 3NT because HCP is fairly precise to determine notrump tricks.
There are many transfers in the structure of notrump openings because
- This makes opener declarer, hiding honors from opponents.
- This saves bidding space. Responder does not show both shape and strength at the same time.
Remind that opener has exposed much information. Therefore, responder is the captain, who makes decisions.
Delayed 2NT openings
After a strong artificial 2♣ or 2♦, opener's 2NT rebid shows a hand stronger than 2NT with 2NT distribution.
The bidding structure is identical to 2NT opening. Responder simply takes opener's excessive points and then bids as if it were a 2NT opening.
- 2♣-2*; 2NT
- 22~23 HCP with 2NT distribution, 2 HCP stronger than 2NT opening.
- 2♦-2*; 2NT
- 24+ HCP with 2NT distribution, forcing to game and 4 HCP stronger.
Responses to 1NT
- 2♣
- Stayman, 9+ points with an unspecified 4+-card major or Garbage Stayman
- 2♦
- Transfer, 5+ cards in hearts.
- 2♥
- Transfer, 5+ cards in spades.
- 2♠!
- Transfer, 6+ cards in clubs or slam try with 5-5 in minors.
- 2NT
- Invitation to 3NT, 8~9− HCP.
- 3♣!
- Transfer, 6+ cards in diamonds.
- 3NT
- Signoff, 9+~14 HCP.
- 4♦!
- 9~15 points, 5-5 or 6-6 in majors.
- 4♠!
- 9+ points, 5-5 or more in minors.
- 4NT
- Quantitative invitation to 6NT, 15 HCP.
- 5NT
- Quantitative invitation to 7NT, 18 HCP.
- 6NT
- To play, 16~17 HCP.
- 7NT
- To play, 19+ HCP.
Strong jump shifts
If responder has not passed, jump shifts are strong. These bids deny a 4-card major side suit. If there is a 4-card major side suit, bid Stayman 2♣ instead because major slams score more than minor slams.
- 3♦, 3♥, 3♠
- Strong jump shift, 16+ points, 5+ cards.
- 4♣
- Strong jump shift, 16+ points, 6+ cards.
Takeout jump shifts
If responder has passed, jump shifts are takeout, showing a maximum 3-suiter with a signleton or void in the bid suit.
These takeout jump shifts deny a 5-card major. If there is a 5-card major, bid Stayman 2♣ for 5-4 majors or transfer for the only major.
Responses to 2NT
- 3♣
- Stayman, 6+ points with an unspecified 4+-card major or Garbage Stayman
- 3♦
- Transfer, 5+ cards in hearts.
- 3♥
- Transfer, 5+ cards in spades.
- 3♠!
- Transfer, 6+ cards in clubs or slam try with 5-5 in minors.
- 3NT
- Signoff, 4+~9 HCP.
- 4♣!
- Transfer, 6+ cards in diamonds.
- 4♦!
- 4+ points, 5-5 or 6-6 in majors.
- 4♠!
- 5-5 or more in minors.
- 4NT
- Quantitative invitation to 6NT, 10 HCP.
- 5NT
- Quantitative invitation to 7NT, 13 HCP.
- 6NT
- To play, 11~12 HCP.
- 7NT
- To play, 14+ HCP.
Major transfer structure
| Weak | Invitational | Game-forcing | Slam try | |
|---|---|---|---|---|
| 4-card major | Pass | Stayman ♣ | ||
| 5+-card major | Transfer ♥/♦ (→ ♠/♥) | SJS or transfer | ||
| 5-4 in majors | Transfer | Stayman ♣ | ||
| 5-5 or 6-6 | ♦ (→♥) | 4♦ | ♥ (→♠) | |
| 6-4 or more | Ignore the shorter major | |||
Strong jump shifts, only available for 1NT opening, require < 4 cards in all other suits.
Minor transfer structure
As notrump games score more than minor games, a hand with no singleton nor void nor biddable major suit is a notrump hand. We only transfer with weak notrump hands. Invitational+ notrump hands are deemed as balanced.
| Weak | Invitational | Game-forcing | Slam try | |
|---|---|---|---|---|
| No singleton nor void | Transfer | 2NT | 3NT | SJS |
| Weak | Game-forcing | Slam try | |
|---|---|---|---|
| One-suiter | Transfer | SJS | |
| 5-5 in minors | Pass | 4♠ | ♠ (→♣) |
| 6-6 in minors | ♣ (→♦) | ||
Quantitative invitations
After a strong notrump opening or a delayed 2NT opening, the 4NT and 5NT responses are quantitative invitations if there is no agreed trump.
- 4NT
- Opener bids a small slam if maximum or signs off otherwise.
- 5NT
- Opener bids a grand slam if maximum or a small slam otherwise.
Quantitative invitation only applies to notrump openings, not rebids. To ask opener for strength, bid clubs for Roudi, the French variation of Checkback Stayman.