When your partner opens the bidding and your RHO makes 
a bid, your bid will depend on what his bid was.  One 
of the options that you will have to consider is a 
Negative Double.   

That means that you cannot make a penalty double, but 
rather the double is used to convey information.  
Basically, responder is indicating tolerance for the 
two unbid suits and not enough strength or length to 
bid freely.  For instance, you hold  XX KJXX KXXX QXX.  
Partner opens one club and RHO bids one spade.  You 
have nine high card points and tolerance for both unbid 
suits, hearts and diamonds.  Also, you don’t have enough 
length in either suit to bid one of them, so you double.  
Partner recognizes that you are making an offensive type 
of bid as opposed to a defensive type of bid.  Normally, 
a double in this situation is considered negative through 
the three level, the only difference is that the higher 
RHO has bid, the more points responder needs to take 
this action.  After 1C – 1S, responder could make a 
negative double with as few as 4 or 5 points.  After 
1C – 2S, the minimum should be 8 or 9, and after 
1C – 3S, responder should have at least 11 – 12 points.  

Before going any further, think about what happens when 
the auction goes 1C – 2S – Pass by responder.  He could 
be showing a bad hand without the requirements for any 
bid whatsoever, OR, he could have some hand with good 
spades and he really wanted to make a PENALTY DOUBLE of 
2S but he couldn’t because his double would have been 
construed as NEGATIVE!  How can you possibly know that 
this has happened?  Well, you really can’t, but there 
are clues.  For instance, you have a nice opening hand 
with support for the unbid suits and shortness in the 
suit bid by the over caller.  It is now more likely that 
partner got caught in this trap and the way you help him 
out is by reopening with a double.  If he has a hand that 
he would have wanted to make a penalty double with, he 
will pass, and if he has a bad hand, he will make the 
cheapest bid that he can make and you will know.

If responder has a long suit (5 or more cards) with some 
substance (KJ10XX or better), he could simply bid the suit.  
If he has 10 or more points and stoppers in the spade suit 
(but not necessarily enough to defend) he could bid no trump, 
and if he has 10 or more points without any stoppers, and a 
hand that is not right for a negative double, he could bid 
three spades. 
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