by Anders Wistrand

The response 1NT over 1 in a suit is called the Negative 1NT because it does not necessarily show a balanced hand.

To bid 1NT you should have between 5 and 9 hcp. Observe that you can be very short in partner's opening suit, sometimes even void. Opener's bidding after the Negative 1NT depends a lot of hands strength and the opening suit.

Don't forget, pass is a good bid after negative 1NT with a weak balanced hand. It is not easy to make the best defence against 1NT. Opponents know very little about Opener's hand.

1 - 1NT

Responder has denied 3 cards in hearts and has not 4 cards in spades. Opener can conclude that responder has at least 8 cards in minors.

With an unbalanced hand opener can bid his second suit for responder to chose. With a strong hand (17+ points) opener shall jump.

What if opener's second suit is spades? If Opener bids 2S he must have a strong hand as it is reverse (Responder can't prefer the first suit on the 2 level). As Responder does not have support for spades (or hearts), the bid must be an invitation to 3NT.

1 – 1NT

Responder has less than 4 cards in spades. New suit from opener is for preference showing 5 spades and a second suit with 4+ cards. Opener can also rebid the spades with 6+ cards.

If opener bids 2NT it is an invitation to 3NT with 18 to 19 points. Opener has to be careful about invitation as responder tends to keep bidding open with minimum strength. Lack of good middle strong cards should be a warning signal.

1 – 1NT

As we open best minor without a 5 card major, 1 does not necessary show a 4 card suit. The 1NT from responder denies 4 cards in any major and thus promises 7+ cards in minors. With a good 4 card diamond suit he would have bid 2D. This means that responder most probably has at least a 4 card club suit.

Any bid in a minor on lowest level is for preference and is not forcing. Any bid in a major is a strong bid and forcing. It can be done with a strong 3 card suit as an invitation to 3NT.

1 – 1NT

Responder has denied 4 card support in all suits but clubs. Indirect Responder shows a 4 card club suit with this 1NT. Usually responder has a little more than minimum when bidding 1NT instead of supporting (a potential 3 card suit) clubs.

Any new suit from opener is forcing to at least 2NT and an invitation to 3NT. Opener normally calculates 4 or 5 tricks in clubs. With a balanced hand and divided hcp strength, opener can also invite with 2NT.