When partner opens the bidding in a suit, you as responder should, if at all possible, bid a suit to a suit – at the lowest level. Avoid bidding notrumps [unless your hand lacks sufficient strength to respond in a new suit at the two- level, in which case you may have to respond 1 NT]. Never respond 2 NT or 3 NT.

Your suit-to-a-suit bid is 100% forcing, so partner will bid again. He will be able to make his planned rebid and you will therefore not miss a fit.

Consider these hands in response to partner’s 1 ♠ opener:

Holding (i) you respond 2 ♣ and await partner’s rebid which will tell you much more. If partner rebids, say, 2 ♦ you will know he is 5- 4 and can bid 4 ♠. Holding (ii) you respond 2 ♦, the cheaper of fours*.

*In any case 1 ♠-2 ♥ shows five+ cards.

Holding (iii) you bid 2 ♥ – note that it would be a mistake to jump to 3 ♥ even though you have a good hand; try to find a fit first, before leaping to show strength.

The only time responder has to bid notrumps in response to a suit opener is when he is weak and has no suit he can bid at the one-level.

Holding (iv) and (v), partner opens 1 ♦; with (iv) you would bid 1 ♠ – not 1 NT which denies a higher-ranking four-card suit; with (v) you bid 1 ♥. Holding (vi) partner opens 1 ♠; finally we have a hand that is forced to bid notrumps (1 NT) to a suit – you lack the strength to bid 2 ♦*.

* Failing the Rule of 14: high-card points + length
of longest suit less than 14.