However, you must use the penalty double wisely. You need to know the proper times to unleash this lethal weapon.
Doubling when your opponents overbid to a sky-high contract
Go ahead and double when you know that the opponents have just gotten beyond their depth. For example, suppose that you pick up the hand shown in this figure:
This hand isn’t very promising because you don’t have high card points (HCP). However, the opponents bid back and forth, and lo and behold, they wind up in a contract of 6♠! The opponents have to take 12 tricks. You look at your hand and see that you have two sure spade tricks. Unless your opponents have a few cards up their sleeve (and then some), they can’t possibly take 12 tricks because your ♠A and ♠K will take two tricks, leaving them 11 at most.
Double! They can’t make 6♠. You have just made a penalty double, telling your partner that good things are about to happen, so please pass.
Passing when you have five or more cards in the suit bid to your right
Like everything else, you can get carried away with too much success. You double a few contracts, you defeat (or “set”) the contracts, and suddenly you think that you created the game of bridge. Be careful. Don’t double unless you have the proper hand. The worst possible moment to double a contract for penalties is when your partner expects a completely different hand type than the one you have. A prime example appears in this figure.
You hear the following as the bidding progresses:
| East | South (You) | West | North (Your Partner) |
| 1♥ | ? |
For example, you have the cards shown in this figure:
The bidding for this hand is humming right along:
| West | North (Your Partner) | East | South (You) |
| 1♠ | Pass | 2♣ | ? |