Defense basics: Which suit to lead

Many a contract stands or falls based on this one decision. But you're shooting blind -- you haven't seen the dummy yet. Making inferences from the bidding and from your hand is a fine art, but here are some basic guidelines, in rough order of preference.

Against no-trump contracts:

Lead your partner's suit. A good suit is always more powerful when led to, rather than led from.

Lead your own longest suit, unless it's one the opponents have bid.

If you have to lead a suit that opponents have bid, lead dummy's, not declarer's, suit.

DON'T lead a short suit that partner hasn't bid.

Against trump contracts:

Lead partner's suit.

Lead a singleton if you have a chance of developing a trump winner. There's little point in leading a singleton if you have, say, KQ of trump, since you have an inevitable trump winner there anyway.

Lead an unbid suit, especially one in which you have an honor sequence.

Lead dummy's suit.

Lead trump if it might prevent dummy from ruffing; e.g. if declarer has shown a long side suit.

If you have significant trump length, lead your longest other suit.

DON'T lead a suit headed by a lone honor or by a tenace.

DON'T lead declarer's side suit.