This Real Deal comes from the 2009 Hunt Valley regional in Maryland.

J 8 7 5
--
A K 10 8 2
J 9 8 7
Take these West cards from a knockout match with both sides vulnerable.

Your LHO opens 1 and RHO responds 1.

I like to enter the auction at a low level, but the opponents have bid my best suit. A takeout double (to indicate spades and clubs) is possible, but feels like a bit much. So, you pass and LHO rebids 1NT. RHO now bids 2. Will you act this time?

It is a bit dangerous, but I would double for takeout. Why this time? In effect, you are in balancing seat. Surely, the 2 bid is signoff--LHO is not bidding again. Partner won't be able to balance (he probably has some heart length). So, it is up to you. Do you really want to make the opening lead against 2? The opponents probably have at least 8 hearts (partner might have overcalled if he had 5). You should have a nice fit your way. You can't make a living by going quietly in such situations.

You make a takeout double and partner bids 3. This is passed around to LHO who competes to 3. This is passed back to you.

West	North	East	South
You
--	1	Pass	1
Pass	1NT	Pass	2
Double	Pass	3	Pass
Pass	3	Pass	Pass
??

Now what? Enough is enough. You should pass. The general rule on these competitive auctions is to push your opponents to the three level, but then call it a day. You lead the A and see:

Vul: Both Dlr: North	A K 2 K 10 2 9 7 5 3 A 3 2
J 8 7 5 -- A K 10 8 2 J 9 8 7

Partner plays the 6 and declarer the jack.

You continue with the K, partner completing a hi-lo and declarer dropping the queen. Now what?

More diamonds will set up dummy's nine, so you shift to a black suit. Which one?

Even though partner bid clubs, that suit can wait. A spade switch is best. If declarer has the Q, nothing you do matters, but if partner has the Q, you want to set up your spade trick. Declarer might have Qx and three low spades. If you switch to clubs, partner will get his K, but declarer will later take the Q and throw a spade on dummy's A. On your spade switch, dummy wins the ace and starts trump. This was the full deal:

Vul: Both Dlr: North	A K 2 K 10 2 9 7 5 3 A 3 2
J 8 7 5 -- A K 10 8 2 J 9 8 7		Q 6 3 A 5 4 3 6 4 K 10 5 4
	10 9 4 Q J 9 8 7 6 Q J Q 6

Your spade switch was indeed necessary. Partner wins his A and is careful to continue spades with the queen. If he carelessly plays a low spade to your jack and dummy's king, he is in trouble. Declarer can draw trump and exit with the third spade to endplay partner to lead from his K. But, when partner exits instead with the Q, the defensive work is done. You will get your J and eventually partner's K for down one.

I live for deals like this. First, you push the opposition from the two to the three level (the most important job in bridge). Then, you don't screw up the good work by overcompeting to 4. Then you use defensive logic (with your partner complying) to go plus on the deal.

These competitive partscore battles "in the trenches" are crucial. Scoring plus 100 (which wins 5 IMPs) is more fun for me than bidding and making a grand slam.