Instead of describing the thrump double, the decision was made to quote the author. The following description is by Mr. Marty Bergen, (website), who invented and devised the thrump double and its application. In case the visitor or bridge student would like to contact Mr. Marty Bergen, he/she can do so by visiting his website.


Contribution by Mr. Mary Bergen

Thrump doubles, as described here, were invented by yours truly. While they certainly are different, experience has shown that they are essential at the three level.

What is a thrump double and why do we need them? The discussion of the bidding on this hand will clue you in.


Once your partner has opened the bidding, you are thinking about 3 No Trump. In fact, I will bet that is the case regardless of which suit your partner opened. You will show your Club and points and hope partner bids No trump sooner or later.

Nice plan. Now suppose that your RHO jumps to 3, 3, or 3 before you are able to make your first bid. Are you going to give up on the 3 No Trump contract you were heading for? If you make the normal 4 bid, do you expect partner to provide the five tricks you will need to bring home 5?

What is my suggestion? Make a negative double. However, instead of defining it as looking for the unbid Major(s), think of it as looking for THRee notrUMP. On most hands where partner has a stopper in the opponent’s suit, you would like him to bid 3 No Trump.

When is this needed? When the enemy’s natural jump overcall reaches 3, we cannot necessarily show our suit without going past 3 No Trump. Here are the 10 auctions where the opponent has made a natural, preemptive jump overcall above 3 and below 3 No Trump.

Opener Opponent Opener Opponent Opener Opponent
1 3 1 3 1 3
1 3 1 3 1 3
1 3 1 3 1 3
1 3

Must you have a solid suit? Absolutely not. A Thrump Double would be totally appropriate after 1 - (3) with:


Now you are the responder after 1 - 3.


Double, hoping that partner bids 3 No Trump.


Forget your Spades. You have Hearts stopped, so bid 3 No Trump.


Once in a blue moon you will have a great hand with a stopper in the opponent's suit. In that case, you can start with a Negative Double and then explore for slam.

Thrump Double Summary

1. Applies when the jump overcall is 3, 3 or 3.
2. Tells opener to bid 3 No Trump when he has a stopper in the opponent’s suit
3. Says nothing specific about responder’s holding in the unbid suits.
4. Almost always denies a stopper in the opponent’s suit.
5. Responder denies a five-card Major that he could have bid at the three level.
6. Promises at least 10 high card points and denies three-card support for opener’s Major.



If you wish to include this feature, or any other feature, of the game of bridge in your partnership agreement, then please make certain that the concept is understood by both partners. Be aware whether or not the feature is alertable or not and whether an announcement should or must be made. Check with the governing body and/or the bridge district and/or the bridge unit prior to the game to establish the guidelines applied. Please include the particular feature on your convention card in order that your opponents are also aware of this feature during the bidding process, since this information must be made known to them according to the Laws of Duplicate Contract Bridge. We do not always include the procedure regarding Alerts and/or Announcements, since these regulations are changed and revised during time by the governing body. It is our intention only to present the information as concisely and as accurately as possible.