A few conventions are worthwhile
Students often ask which conventions they should use. I typically answer, “As few as possible.” But some, which we will study this week, I consider indispensable for a pair who competes in a club duplicate or would like to win in a friendly game with neighbors. First, look at the North hand in today’s diagram. Partner opens one no-trump; what should North do? In the old days, North would have responded three spades, showing five spades and game-going values (or six-plus spades and thoughts of a slam). After South had raised to four spades, East would have led the heart queen, and the defenders would have taken three hearts and one spade.
Now, though, transfer bids into the majors are ubiquitous. North responds two hearts, showing five-plus spades and at least zero points. Here, South has a close decision; he probably just completes the transfer with two spades, but he might jump to three spades, a superaccept indicating four-card support, a doubleton somewhere and a maximum (which is why, with only 15 high-card points, it is questionable). Over two spades, North rebids three no-trump, offering a choice of games, and South retreats to four spades. Over three spades by South, North raises to game. Against four spades, West leads the diamond queen. Now South must resist the temptation to lead a trump, because East can win and shift with effect to the heart queen.
As no doubt you have noticed, South should immediately run clubs and discard two hearts from the dummy on the third and fourth rounds. Although East can ruff the last low, declarer has only three losers: two spades and one heart.