This hand proved a trap for the unwary.  The big question is: do you double or pass when your right hand opponent opens 1NT not vulnerable?

You hold:  ª6 4 3; ©A 8 5; ¨K Q 9; §A Q 9 6

The case for doubling is:

• If partner has eight or more points in a balanced hand you are likely to be defending 1NT going several down undoubled.

• Your points are sitting over declarer.

• If you do not double partner will not be able to punish their escapes.

The case against doubling is:

• You have no attractive lead.

• If partner is weak (0-6 points) you may have difficulty finding a good defence or the opponents can punish you by playing 1NT doubled or redoubled.

• If partner has a reasonable hand and some shape he will bid in fourth position, counting on you to have a decent balanced hand.

My choice would be to pass.

Consider the probabilities.  You have 15 points and declarer 13 (+-1).  So your partner and dummy are going to share 12 points.  Consider the following three possibilities:

1. The likelihood is that they are roughly evenly distributed.  In that case you will play 1NT doubled or the opponents will try to escape.  The only bid you will be happy to double if they do is 2§ and all other bids you will leave to partner.  If the opponents find a 4-4 fit you will not do well doubling and even a 4-3 fit may prove troublesome.  If either dummy or partner have some shape you will not be doubling the opponents.  You will need to find a good defence to beat 1NT doubled.  A club lead will only be effective if partner has §K, approximately 25% of the time [he has 6 points as has dummy and declarer has 13].  A diamond lead should be safe if partner has ¨A or ¨J [approximately 37%] but may be disastrous if he holds neither.  A heart lead is very unattractive and the safest lead is a spade but that is hardly dynamic.

2. If partner hold the balance (8+ points) you will probably get a good result unless they escape to a good fit.  But that will be about 25% of the time, possibly less.

3. If partner has 0-4 points [approximately 25% of the time] you are creating a rod for your back unless he has good distribution and can bid a suit.

Summarising:

• About 25% of the time you will get a good result by doubling.

• About 25% of the time you will get a bad result.
• The remaining 50% you will get a bad result more often than a good result.

That’s enough theory.  This was the actual hand: