North-South vulnerable.  
North deals.
                              NORTH
                              S: 3                
                              H: J 10 6 4    
                              D: A K Q J     
                              C: A 9 7 2 
            WEST                             EAST
            S: A J 9 8 4 2                   S: K 7 5        
            H: 7                             H: A Q 8 5 3  
            D: 9 6 3                         D: 10 8 7 4 2        
            C: 10 5 4                        C: V o i d     
                              SOUTH                         
                              S: Q 10 6
                              H: K 9 2      
                              D: 5         
                              C: K Q J 8 6 3
                  NORTH    EAST    SOUTH    WEST                  
                   1D       1H      2C      Pass   
                   3C      Pass     Pass     3S 
                   4C       4S      5C     Double
                   Pass    Pass     Pass
     Eleven tricks in clubs are there for the taking except for
one small thing - the defense gets to start the play of the hand. 
West has an easy decision, if he doesn't lead a heart (based on
his partner's bid), then he doesn't have one.  Accordingly, West
tables the seven of hearts.  East wins the ace and returns the
eight to signify that he has an entry in the higher ranking of
the other non-trump suits, or in this case, spades.
     West ruffs the heart return and underleads his ace of
spades.  East wins the king and leads another small heart for
West to ruff.  This results in a two trick set worth 500 points
for the East-West pair.  This is an excellent result no matter
what form of competition you are involved in.  In the actual
situation, the game was team of four and the contract at the
other table was three no trump in the South, down three after
West led his fourth best spade and the defense ran off six spade
tricks and the ace of hearts.  The contract was not doubled and
East-West only gained 300 points.
   What went wrong with the auction?  All went well until North
decided to take action over three spades.  He has no reason to
bid.  After a reasonable pass by North and East, South will no
doubt compete with four clubs.  If East decides to raise spades
the North-South partnership will be in better position to
evaluate their defensive prospects and will more than likely
double.  In any event, they are headed for a better score.
     There are two important points to be learned from this hand. 
Don't bid the same values twice.  North has already shown his
complete hand when he supports clubs at the three level.  Bidding
four clubs freely (that is when partner is guaranteed to have
another chance to bid) is truly an invitational bid as opposed to
being competitive.  
     Also, when defending against a suit contract, don't
underlead a side suit ace unless you have a specific reason.  In
this case, partner had raised spades and returned a high heart
for West to ruff.  This was a strong indication that he had a
high spade honor (the ace or the king).  Since the defense would
only score one spade trick because of the singleton in dummy, it
was reasonable to underlead the ace to reach partner's hand for
another heart ruff.  
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