DONT

DONT (Disturbing Opponents' No Trump) is a conventional defense to a 1NT opening. Philosophically, it aims to interfere with an opposing 1NT as frequently as possible. How? Unlike other popular 1NT defenses, DONT lets you show all one- and two-suited hands at the two-level. More on this in "The Benefits" section below.

Double shows a single suited hand. Any two-level overcall promises that suit plus a higher one (at least 5-4). Lastly, 2 simply shows spades.

Overcall	Meaning
Double	Any one suit (normally 6+ cards), relay to 2.
2	Clubs and a higher suit (at least 5-4 or 4-5).
2	Diamonds and a higher suit (at least 5-4 or 4-5).
2	Hearts and spades (at least 5-4 or 4-5).
2	Spades (normally 6+ cards), weaker than a double followed by a 2 rebid.

The strength required for a DONT overcall is influenced by vulnerability and position (direct seat vs. balancing). However, bridge authors generally seem to agree that DONT can be used with light shapely hands. 8 points might qualify for a direct overcall at favorable vulnerability. The requirements may be even less when balancing.

Imagine holding the following hands after RHO opens 1NT.

Hand A 10 5 2 K J 10 9 4 3 A J 3 5

Hand B Q J 10 9 3 2 A 10 8 6 7 5 8

Hand C K 10 7 6 2 2 K 10 6 5 4 2 5

With Hand A, you can double with the intention of bidding 2 at your next turn.

Holding Hand B, you can bid 2 immediately to show spades and a weak hand. With more points, you would double first and then bid spades.

It's also worth mentioning here that 6-4 shape generally isn't worth treating as a two-suiter. If you bid 2 in this example, partner will simply pass with something like 2-2-4-5 shape. It will be a long car ride home if you share one.

Lastly, Hand C is light in high cards but big in shape — it's worth a 2 overcall. As the late great Grant Baze used to say, "6-5 come alive."

The Benefits

Other defenses like Cappelletti or Multi-Landy require you to bid 2/ with that major and an unspecified minor. In those situations, partner is forced to bail into the three-level if he can't tolerate your major suit.

By comparison, DONT never forces you that high. When you overcall, partner can always pass-or-correct at the two-level.

How much does this matter? In his book "Multi-Landy: The Killer Defense Versus One Notrump", David Oakley provides the odds of various hand types after an enemy 1NT:¹

• A 5-card major and a 4-card or longer minor, 29%
• 6-card or longer minor, 19%
• At least 4-4 in the majors, 18%
• 5-card or longer minor plus a 4-card major, 17%
• A 6-card or longer major, 15%
• Strong hand, 2%

These percentages represent Multi-Landy hand types but are still germane here. Oakley's simulations suggest that you'll hold a major-minor two-suiter for roughly 46% of your overcalls (29% + 17%). DONT lets you stop at the two-level with these hands. Other conventions can't.

The Drawbacks

DONT sacrifices a natural penalty double of 1NT to show one-suited hands instead. In his book "To Bid Or Not to Bid", Larry Cohen argues that this isn't a big deal:²

Some methods allow you to make a penalty double of one notrump. Are we bothered by the fact that D.O.N.T. doesn't allow for this? Not at all! Penalty doubles of one notrump are unappealing and ineffective. Choosing an opening lead and defending against one notrump doubled is one of the most difficult challenges in bridge. Furthermore, it's rare to be dealt a strong hand when an opponent also has a strong hand. And even if you can double and defeat one notrump, the opponents will often have a place to run and the mechanism to get there.

But yet... while a penalty double of a strong 1NT is rarely needed, it's indispensible against a weak 1NT. Cohen himself therefore recommends a penalty-oriented defense to the latter.³ Marty Bergen, DONT's inventor, suggests playing DONT only against strong 1NT openings of at least 14+ HCP.⁴

If you adopt DONT, then, you should still consider (and remember!) a defense like Cappelletti against weak no-trumpers.

Responses by the advancer (overcaller's partner) are fairly natural. 2NT is the only forcing artificial bid, showing roughly 10+ points. Multiple 2NT structures exist — the one below is ascribed to the detailed DONT article on Larry Cohen's website.⁵

After a Double

After a double, advancer is expected to bid 2, which is a pass-or-correct relay. Advancer may, however, skip 2 to bid a strong 6-card suit of his own.

Response	Meaning
2	Asks partner to pass or correct.
2	6+ diamonds, non-forcing.
2	6+ hearts, non-forcing.
2	6+ spades, non-forcing.

Partner 8 7 J 10 5 A 2 A J 10 7 5 2

You 10 4 3 2 K Q 6 8 5 3 Q 7 6

LHO 1NT Pass

Partner Dbl1 Pass3

RHO Pass

You 22

¹ Showing a single-suiter.
² Dutifully completing the relay to 2.
³ I've got clubs.

Partner K Q 5 10 A K 10 6 3 2 9 8 2

You 10 4 3 2 A Q 9 7 6 8 Q 7 6

LHO 1NT Pass

Partner Dbl1 23

RHO Pass Pass

You 22 Pass4

¹ Showing a single-suiter.
² Completing the relay. Note that this hand isn't good enough to unilaterally bid 2.
³ Correcting to his suit.
⁴ Not thrilled with diamonds, but bidding again would be unjustified.

Partner 8 7 A J 10 9 4 K Q 10 8 5 2

You A Q J 9 6 3 4 3 2 Q 8 5 9

LHO 1NT

Partner Dbl1

RHO Pass

You 22

¹ Showing a single-suiter.
² Worth bypassing the relay with a great spade suit. Even though partner's suit is unknown, the singleton club implies a legitimate risk of getting dropped in 2.

After a 2 Overcall

In response to 2, advancer typically passes with support for clubs, or bids 2 to ask for overcaller's second suit.

Response	Meaning
Pass	To play.
2	Denies club support. Asks overcaller to pass or correct.
2	6+ hearts, non-forcing.
2	6+ spades, non-forcing.
2NT	Artificial and forcing. Overcaller's rebids: 3 with a minimum 3 with diamonds and a maximum 3 with hearts and a maximum 3 with spades and a maximum
3	Preemptive raise, non-forcing.

Partner 8 7 A 5 A 9 7 2 A J 10 7 5

You 10 4 3 2 K 6 5 4 8 5 Q 7 6

LHO 1NT

Partner 21

RHO Pass

You Pass2

¹ Showing clubs and a higher suit.
² Promising 3-card support.

Partner 8 7 A 9 7 2 A 5 A J 10 7 5

You 10 4 3 2 K Q 5 8 7 6 4 9 2

LHO 1NT Pass

Partner 21 23

RHO Pass

You 22

¹ Showing clubs and a higher suit.
² Wanting to play anything but clubs.
³ Not necessarily a better fit, but some underwhelming outcomes will accompany the good.

After a 2 Overcall

Advancer typically passes with diamond support, or bids 2 looking for overcaller's major.

Response	Meaning
Pass	To play.
2	Denies diamond support. Asks overcaller to pass or correct to spades.
2	6+ spades, non-forcing.
2NT	Artificial and forcing. Overcaller's rebids: 3 with an equal-length or shorter major and a minimum 3 with a longer major and a minimum 3 with hearts and a maximum 3 with spades and a maximum
3	6+ good clubs, non-forcing. Rare since advancer is ignoring overcaller and introducing his own suit at the three-level.

Partner 8 7 K Q 9 5 2 Q 8 7 4 3 6

You Q 4 3 2 J 10 4 K 2 A 10 8 5

LHO 1NT Pass

Partner 21 Pass3

RHO Pass

You 22

¹ Showing diamonds and a higher suit.
² Asking for the major.
³ Passing with hearts.

Partner 8 7 6 K Q 9 5 A J 7 4 3 6

You A 4 3 A J 4 10 5 2 A 10 8 5

LHO 1NT Pass

Partner 21 33

RHO Pass Pass

You 2NT2 34

¹ Showing diamonds and a higher suit.
² Artificial and forcing. Hoping for a 5-3 major-suit fit.
³ Showing an equal-length or shorter major and a minimum.
⁴ Signing off. Not worth the gamble of finding partner 5-5 in the red suits.

After a 2 Overcall

Advancer normally passes or corrects to 2.

Response	Meaning
Pass	To play.
2	To play. (Denies heart support.)
2NT	Artificial and forcing. Overcaller's rebids: 3 with equal-length or shorter spades and a minimum 3 with longer spades and a minimum 3 with equal-length or shorter spades and a maximum 3 with longer spades and a maximum
3	6+ good clubs, non-forcing.
3	6+ good diamonds, non-forcing.

Partner Q 9 8 7 4 A K 9 5 J 6 5 3

You K J J 10 K 9 8 7 6 5 10 9 8

LHO 1NT

Partner 21

RHO Pass

You Pass2

¹ Showing hearts and spades.
² Passing with equal length in the majors. Not a pretty result but there's no way of knowing partner's exact shape.

After a 2 Overcall

Advancer usually passes. He should only bid a new suit with 6+ good cards and no spade support.

Response	Meaning
Pass	To play.
3	6+ good cards, non-forcing.
3	6+ good cards, non-forcing.
3	6+ good cards, non-forcing.
3	Natural, non-forcing.

Partner K Q 9 8 7 5 Q 10 8 6 4 3 2

You A J 10 4 K 5 4 3 5 10 8 6 4

LHO 1NT

Partner 21

RHO Pass

You 32

¹ Showing a lighter hand than doubling and then bidding spades.
² Raises should be conservative, given partner's weakness.

A competitive auction can unfold in several ways. While not exhaustive, these common sequences are summarized below:

1. Partner doubles, and RHO redoubles.
2. Partner doubles, and RHO bids a suit.
3. Partner bids a two-suiter, and RHO doubles.
4. Partner bids a two-suiter, and RHO bids a suit too.

Partner Doubles, and RHO Redoubles

LHO 1NT

Partner Dbl*

RHO Redbl

You ?

RHO's redouble normally shows values of some kind. When this happens, the 2 relay is off.

Bid	Meaning
Pass	Willing to let partner run to his suit.
Any new suit	6+ cards, non-forcing. This includes 2.
2NT	Still the artificial ask, albeit highly unlikely.

Partner Doubles, and RHO Bids a Suit

LHO 1NT

Partner Dbl

RHO 2//*

You ?

Bid	Meaning
Double	For takeout. Asks partner to either pass with the opponents' suit, or bid his own.
Any new suit	6+ cards, non-forcing. Additional length or strength is needed to bid at the 3-level.
2NT	Still the artificial ask, albeit highly unlikely.

The following example is from "25 More Bridge Conventions You Should Know" by Barbara Seagram and David Bird:⁶

10 8 5 2 K J 6 4 J 3 A 8 7

LHO 1NT

Partner Dbl*

RHO 2

You ?

If you choose to compete now, you must double to ask partner's suit — and hope it isn't diamonds. (Seagram and Bird recommend that double is always for takeout when partner's suit is unknown.)

Partner Bids a Two-Suiter, and RHO Doubles

LHO 1NT

Partner 2//*

RHO Dbl

You ?

Bid	Meaning
Pass	Shows tolerance for partner's suit.
Redouble	SOS, asking partner to bid his other suit.
Any new suit	6+ cards, non-forcing. The exception is if partner has bid 2 and advancer simply wants to run to 2. Additional length or strength is needed to bid at the 3-level.
2NT	Still the artificial ask, albeit highly unlikely.

Partner Bids a Two-Suiter, and RHO Bids a Suit Too

Bid	Meaning
Double	For takeout — asks partner to bid his second suit.
Any new suit	6+ cards, non-forcing. Additional length or strength is needed to bid at the 3-level.
2NT	Still the artificial ask, albeit highly unlikely.

DONT Over 2NT

DONT can be played over a natural 2NT opening, although the strength and shape requirements become stricter. Two-suited overcalls should promise at least 5-5 shape, and perhaps even more depending on vulnerability.

DONT Runouts

DONT can also be used as an escape system when partner opens 1NT and gets doubled for penalty. Now redouble shows a single-suited hand as a relay to 2. And all two-level bids have the same DONT meanings as above, albeit with less shape requirements for practicality.

Delayed DONT

Marty Bergen also suggests that DONT can also be used anytime the opponents bid 1NT. For example:

LHO 1

Partner Pass

RHO 1NT

You ?

The same DONT overcall structure would apply here. In fairness to Marty, you can buy his booklet DONT, DONT Runouts, and Delayed DONT to read the full details.

DONT was invented by American expert and teacher Marty Bergen. The convention was originally named "Bergen Over No-Trump" in the 1980s, but the DONT moniker prevailed over time.

As it's intended to maximize the volume of overcalls over 1NT, DONT reflects Marty's school of aggressive competitive bidding.

• ¹ Oakley, David. Multi-Landy 2nd Edition. Toronto, Master Point Press, 2018.
• ² Cohen, Larry. To Bid or Not to Bid. Toronto, Master Point Press, 2002.
• ³, ⁵ Cohen, Larry. (2004, March 4). DONT.
• ⁴ Bergen, Marty. DONT, DONT Runouts, and Delayed DONT.
• ⁶ Seagram, Barbara and David Bird. 25 More Bridge Conventions You Should Know. Toronto, Master Point Press, 2003.