Neither side vulnerable.  
East deals.
                              NORTH
                              S: 5 4 3                 
                              H: Q 10 8 6 4 2
                              D: K J 9 6     
                              C: Void    
            WEST                             EAST
            S: A 2                           S: J            
            H: A J                           H: K 7 5 3    
            D: A Q 10 4                      D: 8 7 3 2           
            C: A 9 8 6 3                     C: J 10 5 4    
                              SOUTH                         
                              S: K Q 10 9 8 7 6
                              H: 9          
                              D: 5         
                              C: K Q 7 2
          The Bidding:
                   EAST   SOUTH     WEST   NORTH                  
                   Pass    4S      Double   Pass
                   Pass    Pass
	Opening Lead: AH
     The player sitting in the West seat has a number of
difficult decisions to make during the five or six minutes it
takes to bid and play this hand.  The first problem is what to
bid over South's four spade call.  Many partnerships play that a
double in this instance is penalty and four no trump is a three
suit take out bid.  Holding only two hearts is sufficient reason
to avoid four no trump.  While five clubs is also an alternative,
I think it comes down to double or pass.  At match point
duplicate competition, I would pass.  If you defeat four spades
you should get a decent score and a double could very easily
become a bottom.  At team competition it is right to double.  The
opposition is already in game so it is not going to cost much if
the contract is made.  From your perspective, that is an unlikely
result.
     The second problem is the opening lead.  A good player will
not under lead a non-trump ace in this situation, and there is
little information available except for the high probability of
strange distribution all around.  It could be right to start with
the ace of spades.  For one thing, it won't get trumped.  On the
other hand, you don't want to smother the singleton king, if your
partner happens to have that holding.
     Of the other three suits, the ace of hearts seems the least
likely to be trumped by declarer, and if partner can encourage
you might score a quick ruff.  Nothing else looks attractive so
West leads the ace of hearts and gets a chance to see the dummy. 
Partner does play an encouraging seven and declarer plays the
nine.  A second heart lead will probably establish the heart suit
in dummy and it is not likely that declarer can do that by
himself, which brings us to the third problem, what card does
West play to trick two?
     When this hand was actually played, West, fearing club ruffs
in the dummy, played the ace of spades at trick two and the deuce
of spades at trick three.  Declarer won the third trick in hand
and led the five of diamonds.  West won the ace and found himself
with yet another problem.  A heart lead would establish the suit
for declarer.  A diamond lead would allow for two club discards
from  the South hand.  If the ace of clubs was led, declarer
would trump in dummy and discard the last losing club on the king
of diamonds.
     It turns out that the lead of a low club will set the
contract, but that is not easy to see.  West led a low diamond
and declarer played the jack from dummy discarding a club from
hand.  Another club went away on the king of diamonds.  A heart
was trumped and the king of clubs led and covered by the ace,
ruffed in dummy, at which point declarer claimed his doubled
contract.
     As in most difficult hands, the mistake was really made at
trick two.  If declarer cashes the ace of diamonds prior to
playing the ace of spades and another spade, there will be no
problem later in the hand.  With three tricks home, if West finds
himself on lead he will have already defeated the hand one trick. 
As it turns out, declarer is unable to set up and enjoy the
hearts in dummy, and there are not enough resting places to cover
all of the losing clubs.
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