A First Look

In this example of double asymmetry, North/South might consider game in either spades or notrump.

If South declares the 4 ♠ contract, all is well - the opponents will get their three black winners and no more.

If North declares 4 ♠, though, the club lead sets it, because the defense gets two clubs, the trump ace, and a club ruff.

South cannot make 3 NT on a heart lead from West. Twist and turn as he might, he cannot avoid losing two hearts, two clubs, and a spade before he can run his nine apparent tricks.

On the other hand, if North declares in 3 NT, he cannot be set by a heart or any other lead.

On a low heart lead, North wins West's ♥ 10 with the ace, and leads the ♠ J. East has to duck this, to keep declarer from running five spades when he gets in next. North continues with a spade and East can safely win this trick, leading to this position:

			♠ — ♥ K 9 7 ♦ A Q J 4 ♣ J 9 6
♠ — ♥ 6 5 3 ♦ K 10 9 7 5 ♣ A Q						♠ 9 ♥ Q J 4 ♦ 8 2 ♣ 8 7 5 3
			♠ K Q 10 8 ♥ — ♦ 6 3 ♣ K 10 4 2

East cannot attack hearts himself here, because that would give declarer a third stopper. So he has to lead a club to West's queen.

West continues with a heart, ducked to East, and East again cannot lead hearts, holding ♥ Q-4 and North holding ♥ K-7. West gets in one more time to lead hearts, but North still has the ♥ K, and the defense fails to collect its five tricks before declarer makes his nine.