This is a conventional method used in bridge bidding and which was devised by Mr. Marty Bergen and published by Mr. Larry Cohen. The DONT conventional method was first published in the magazine Bridge Today in Marty Bergen's column in the issue of September / October 1989, pages 23 to 29.
This convention is sometimes referred to as Bergen Over No Trump, but has been accepted into the language of the bridge community as simply D.O.N.T. or DONT, an acronym for Disturbing Opponent's No Trump. Compare: Bergen Over Weak No Trump.
The conventional method is employed either in the direct or in the balancing seat after an opponent opens a strong No Trump opening bid, which has been announced as containing a minimum of 14 plus high card points to a maximum of 18 high card points.
Additional Employment of D.O.N.T.
It must be noted that the original concept has been adjusted and/or modified to be employed in other, definite bidding sequences, such as those listed below. These modifications carry no official designation, but are features of partnership agreements.
Note: This conventional method may also be employed following a 1 No Trump opening bid by an opponent, which is announced as containing 10-12/13 high card points and promising balanced distribution. See below.
Note: This conventional method may also be employed following a 2 No Trump opening bid by an opponent, which is announced as containing 20-21/22 high card points and promising balanced distribution.
Note: This conventional method may also be employed following a strong 1 Club opening bid, which generally describes a holding containing 16/17 plus high card points. See below.
Note: Continuances by advancer are per partnership agreement with all methods.
Any No Trump bids which show 13 high card points or less are to be considered Weak No Trump openings. The reason behind this feature of the convention is the fact that the D.O.N.T. convention does not incorporate the penalty double. If the opponents open a Weak No Trump, then the partnership should have the penalty double as a useful instrument. See: Bergen Over Weak No Trump.
The conventional method of D.O.N.T. can be employed either as a direct overcall or in the balancing seat after two consecutive passes.
The main feature determining the decision to interfere with a D.O.N.T. bid is the actual distribution of the holding, not high card points. It is the distribution of the hand which allows one partner to begin disturbing the No Trump opening of the opponents. Following is a list of calls over a No Trump opening (14-17/18 points) of an opponent and the meaning of each call as devised by Mr. Marty Bergen.
Opponent Overcaller Meaning 1 NT Double Shows a one-suited hand with at least a 6-card suit or longer. 2 Shows Clubs and an unspecified higher-ranking suit. 2 Shows Diamonds and an unspecified higher-ranking suit. 2 Shows both Major suits, neither suit preferable. 2 A natural bid showing at least a 6-card Spade suit or longer. A 2 Spades overcall promises a weaker holding than a double followed by a 2 Spades rebid.
When a partnership employs the D.O.N.T. convention, the partner (advancer) hopes for a 5-5 distribution, which should be the case if the partnership is vulnerable. If the partnership has a favorable vulnerability, then a 5-4 distribution is also acceptable. Also, if the partnership is vulnerable, then the honor cards (working values) should be located mainly in the distributional suits, and the point count should be relatively stronger when compared to favorable vulnerability.
Note: For partnerships employing the Losing Trick Count method the recommendation is a maximum of 8 losing tricks by favorable vulnerability and a maximum of 7 losing tricks by unfavorable vulnerability.
It has been argued that it is preferable for the partnership reaching either a partscore of even a game contract against an opposing No Trump bidder that the No Trump bidder be seated at the right of the declarer. The reason is that the partner of the No Trump bidder then has to lead through the No Trump holding, giving the declarer a (possibly) added advantage.
There are several partnership agreements regarding the double and a suit rebid. Some partnerships will double and rebid a suit on the holding:
Opponent Overcaller Meaning 1 NT Double Shows a one-suited holding with a 6-card suit or longer. 2 Shows a 6-card Spade suit or longer, range unknown.
QJ10864 K2 8743 5
Note: Other partnerships have agreed on the following:
Opponent Overcaller Meaning 1 NT Double Shows a one-suited holding with a 6-card suit or longer. 2 Shows a 6-card Spade suit or longer, maximum Weak Two bid in values or better.
KJ10764 94 K3 KQ2
However, most all partnership agreements have the following understanding with the following holding:
Opponent Overcaller Meaning 1 NT Double Shows a one-suited holding with a 6-card suit or longer. 3 Shows a 6-card Spade suit or longer; opening or better values, but non-forcing.
AQJ10853 9 K3 KQ5
And most all partnerships have the following understanding with the following holding:
Opponent Overcaller Meaning 1 NT 3 Shows a normal preemptive bid with corresponding values.
AJ108764 6 J1094 7
However, it must be noted that some partnerships would first double and then rebid the Spade suit, especially if they were vulnerable. It must be brought to the attention of the bridge student that a double would allow the opponents to continue their bidding auction almost without any interruption because the double has not taken up any bidding space. In the above example, the most the No Trump bidder could hold would be KQ95 in the Spade suit.
Example of Auction When Opponents Open 2 No Trump
Opponent Overcaller Meaning 2 NT Generally shows values of 20-21/22 points and balanced distribution. 3 D.O.N.T. conventional method showing the specified Club suit and one unspecified higher-ranking suit. The trick-taking ability should be stronger than employment over a 1 No Trump opening bid by opponent.
AK8764 6 J10 QJ985
Note: The recommended distribution should be a minimum of 5-5 in both suits by any state of vulnerability. The working values should be in the two suits to avoid too many losing tricks in these two suits.
Note: Continuances are identical to the employment of D.O.N.T. over a 1 No Trump opening bid.
Continuances by Advancer
Once the partnership has established an understanding regarding the double, the partner (advancer) of the doubler has several options.
1. The partner will normally bid 2 Clubs, which is a relay bid, the cheapest possible bid, asking the doubler to name his suit. 2. In the case that the partner has an extremely good suit of his own, the partner will bid that suit. Any independent suit must have at least 6 cards with working values in that particular suit.
1. The partner will normally bid 2 Clubs, which is a relay bid, the cheapest possible bid, asking the doubler to name his suit. For example:
Opponent Overcaller Opponent Advancer Meaning 1 NT Double Shows a good 6-card suit or better with outside values. Pass 2 Relay bid. Pass 2 // The opener shows his suit, which should be at least the following: KQ10974, meaning that the suit should hold no more than 1 to 1.5 Losing Tricks.
2. In the case that the partner has a good hand, meaning 15 plus high card points and a balanced to semi-balanced holding, then the partner is allowed to pass, converting the double to a penalty double. This situation may arise when the opponents are vulnerable, and the partner is able to discern the suit of his partner, the Doubler, early in the play and has the stopping power to continue leading up to his partner's suit. A knowledge of the method of scoring is all important. Since the partnership normally will not have game against a No Trump opening, down two vulnerable and doubled will show a good result.
In the following bidding sequence, the partner has several options open to him.
Opponent Overcaller Opponent Advancer 1 NT 2 Pass
1. If the partner has good Club support and few values, then he will pass. 2. The partner can make a relay bid of 2 Diamonds, asking the overcaller for his second suit. If the second suit is Diamonds, the overcaller will pass. Game is most unlikely in a Minor suit. 3. The partner may have a good suit of his own, which he will then bid, showing no interest in the suit of his partner, the overcaller. The partner will simply bid 2 Hearts, 2 Spades, or 3 Diamonds, which are not relay bids according to the partnership understanding. 4. The partner may raise the 2 Clubs overcall, but does not show any strength but is only continuing the disturbance to the opponents. This continuation of the disturbance of the bidding process may occur also even if the partner of the No Trump bidder decides to enter the auction with perhaps a 2 Diamond Jacoby Transfer bid to Hearts. 5. The partner may bid 2 No Trump, which is an attempt at game, and also forcing the overcaller to describe his hand further by naming his second suit on the Three Level. Although this bid of 2 No Trump is available, this situation will hardly ever present itself. The percentage that the partner of the No Trump bidder holds zero tricks is very small, and that is the reason why game is almost improbable.
The bidding sequences and the options of the partner of the overcaller are similar if the overcaller bids 2 Diamonds.
If the overcall is 2 Hearts, then the partner also has several options.
Opponent Overcaller Opponent Advancer 1 NT 2 Pass
1. The partner simply passes if he prefers Hearts over the second-known suit Spades. 2. The partner can bid 2 Spades if he prefers Spades over Hearts. 3. The partner can respond with 3 Clubs or 3 Diamonds if he has a good 6-card suit or better and believes his hand holds more promise of making the contract in a Minor suit than in either of the two Major suits. The overcaller is expected to pass. 4. The partner can respond by bidding 2 No Trump requesting a further description regarding the holding of his partner. The partner, again, should have a minimum of 15 high card points and a balanced to semi-balanced hand. This bid is game-invitational. 5. The partner can raise and bid either 3 Hearts or 3 Spades, but this is not forcing to game, but a continuation of the disturbance. This is generally the case if the Partner is especially weak and believes that the opponents may have game. This is the reason for the guideline stated below:
Two Guidelines to Assist the Bridge Student
1. When the partner raises a known suit, it is simply a weak raise and absolutely non-forcing. 2. If the holding indicates that game is a possibility, then the first bid by the partner must be a 2 No Trump response.
Judgment should be applied to every situation, as well as logic and common sense along with that undefined card sense. The following example should illustrate this point.
J72 A1093 AQ962 8
KQ9864 Q 85 QJ94
East South West North 1 NT 2 Pass 2 Pass 4 Pass Pass Pass
South informed North that he holds a two-suited hand, but North has a good long Spade suit. South uses his judgment and common sense, and bids game in Spades, knowing that they have 9 Spades between them. This is indeed a situation, which will not occur often, although East does indeed have one Spade stopper and a No Trump range, because a holding of A105 is not considered adequate.
Examples of Bidding Sequences
In the case of the following bidding sequence:
East South West North 1 NT 2 Double
North can enter the auction by showing preference several ways.
1. If North passes, then North indicates that he would prefer to play in Clubs. 2. If North bids another suit, then North wants to play in the suit named. 3. If North redoubles, North is asking for the second suit of his partner, South.
In the following example, the options open to North, after his partner overcalls in one of the Minor suits, are changed if the partner of the 1 No Trump bidder enters the auction with a suit of his own.
East South West North 1 NT 2 2
After West has bid Spades, North is aware of the two suits in the hand of his partner, South, which are Diamonds and Hearts. If South had bid 2 Clubs, then his holding could be either Clubs and Diamonds or Clubs and Hearts. North, however, has several options open to him.
1. If North passes, then North is not interested in entering the auction. 2. If North bids another suit, then North wants to play in the suit named. 3. If North doubles, this indicates interest in entering the auction and wishes to know the second suit. This is a takeout double.
In the following example:
East South West North 1 NT 2 2 NT
If North doubles the 2 No Trump bid, this is a takeout double and South should bid his other suit. North has decided that entering the auction on the three level is acceptable. However, if East/West bid 3 No Trump in the above example, any double by North/South is then a penalty double.
If the overcall is 2 Hearts:
North knows both suits of his partner.
1. If North doubles, this is then a penalty double, not a takeout double. 2. North can enter the auction with 3 Hearts or 3 Spades.
In the following example:
East South West North 1 NT Double Redouble
North realizes that 1 No Trump redoubled equals game. North has several options available.
1. If North passes, then this pass is a request that South name his 6-card or longer suit. 2. If North bids a suit, then North has a good 6-card or longer stand-alone suit.
In a situation where sufficient information can be exchanged to consider game after a 1 No Trump opening, the D.O.N.T. convention provides a method of exploring this possibility. Considered first is the 2 Clubs overcall.
East South West North 1 NT 2 Pass 2 NT Pass
Any 2 No Trump bid by the partner of the overcaller is absolutely forcing, and requests further descriptive information. In the above example, South can further describe his hand.
1. A 3 Clubs bid by South shows minimum values with Clubs and a higher-ranking suit. If North bids 3 Diamonds, then North is asking for the second suit. If the second suit happens to be Diamonds, then South will pass because game in a Minor suit is very unlikely after a 1 No Trump opening. Otherwise, South will bid his second suit. 2. A 3 Diamonds rebid by South shows maximum values with Clubs and Diamonds and is game forcing. 3. A 3 Hearts rebid by South shows maximum values with Clubs and Hearts, and is game forcing. 4. A 3 Spades rebid by South shows maximum values with Clubs and Spades, and is game forcing.
The D.O.N.T. convention suggests that maximum values by favorable vulnerability should be a minimum of 11 high card points and a 5-5 distribution. By unfavorable vulnerability, the suggestion is to have a minimum of 13 high card points and a 5-5 distribution. Anything less should be considered minimum values by any vulnerability.
Considered second is the 2 Diamonds overcall.
East South West North 1 NT 2 Pass 2 NT Pass
South is forced to describe his holding further. South can do so with the following rebids:
1. A 3 Clubs rebid shows minimum values with Diamonds and Hearts. 2. A 3 Diamonds rebid shows minimum values with Diamonds and Spades. 3. A 3 Hearts rebid shows maximum values with Diamonds and Hearts. 4. A 3 Spades rebid shows maximum values with Diamonds and Spades.
The rebids of 3 Hearts and 3 Spades are absolutely game forcing. North may not discontinue the bidding until game has been reached.
D.O.N.T. Over Mini-No Trump
This conventional defense method can be employed by bidding systems, which employ opening bids of 1 No Trump having a range of 10-12/13 high card points (the so-called mini-No Trump). The fundamental idea is that the two opponents can compete also against this range. The main difference is that the overcaller promises values for an opening bid. Thus the advancer is able to convert the double by partner into a penalty double, a feature, which is not possible in the original version.
The overcall shows, as in the original concept, a two-suited holding with 5-5 by unfavorable vulnerability and preferably 5-4 by favorable vulnerability.
The actual structure for the overcaller is as follows against a mini-No Trump opening bid of 10-12/13 high card points.
Opponent Overcaller Meaning 1 NT Double Promises full opening values and intended as a penalty double. The advancer is expected to pass. 2 Shows any single-suited holding. The advancer bids 2 to allow the doubler to either pass or correct. 2 Shows Diamonds and an unspecified higher-ranking suit, such as Hearts, Spades, or Clubs. Note: The main difference is that the highest-ranking suit in this sequence is Clubs. 2 Shows both Hearts and an unspecified higher-ranking suit, such as Spades, or Clubs. 2 Shows Spades and Clubs.
Example 1 Opponent Overcaller Meaning 1 NT 2 Shows Diamonds and an unspecified higher-ranking suit, such as Hearts, Spades, or Clubs.
65 8 QJ985 KJ1087 Continuances: the advancer would bid 2 with no support for Diamonds and the overcaller would correct to Clubs. If the advancer has at least a 3-card support for Diamonds (a known fit), then the advancer would raise Diamonds accordingly.
Example 2 Opponent Overcaller Meaning 1 NT 2 Shows Spades and Clubs.
QJ985 8 94 KJ1087 Continuances: the advancer would pass with at least a 3-card support in Spades or correct to Clubs. Note: since the bid of 2 No Trump in this bidding sequence is idle, then the partnership can assign a personal meaning. In those rare cases, in which the advancer holds only a 2-card support in both known suits, then the partnership can agree on a No Trump final contract.
Word of Caution
As a note of caution for all bridge players participating in sanctioned bridge tournaments it is important to check the convention card as to the application of the D.O.N.T. conventional method.
This note of caution is necessary since some partnership agreements include the understanding that the D.O.N.T. conventional method only applies in the fourth seat. For immediate overcalls following an opening bid by opponent of 1 No Trump, weak or strong, the partnership understanding may be that another conventional method is employed, such as Multi Landy or Cappelletti.
Note: It is the obligation, in the instance that no other regulation exists, of the individual player to determine as to whether such an agreement is being employed.
D.O.N.T. Following Strong Club Opening Bids
When the opponents open with 1 Club and the opening is defined as a Precision Club or an opening bid of 1 Club of any strong Club System, then the significance of this bid is important in that it shows a minimum of 17 high card points. The employment of the D.O.N.T. conventional method can also be employed following this strong Club opening bid.
The overcall is always in the immediate seat since the responder to the strong Club opening bid is forced to bid if the player in the immediate seat passes. For the opposing side then to enter the auction becomes rather ineffectual.
The overcalls are described below.
Opponent Overcaller Responder Advancer Meaning 1 Shows a strong Club opening bid with a minimum of generally 17 high card points without distributional points. Double Pass A double shows any single-suited holding. The suit is unspecified. 2 Continuance: the advancer bids 2 Clubs. The overcaller either passes or corrects. 2 Shows Clubs and an unspecified higher-ranking suit. 2 Shows Diamonds and an unspecified higher-ranking suit, either Hearts, Spades, or Clubs. 2 Shows Hearts and an unspecified higher-ranking suit, either Spades, Clubs, or Diamonds. 2 A natural bid showing at least (preferably) a 6-card Spade suit or longer.
Example Opponent Overcaller Responder Advancer Meaning 1 Shows a strong Club opening bid with a minimum of generally 17 high card points without distributional points.
K AKJ984 K8 KJ432
QJ985 52 AQ1076 A
642 Q10 532 98765
A1073 763 J94 Q10 2 Pass Shows Diamonds and an unspecified higher-ranking suit, either Hearts, Spades, or Clubs. 2 The responder holds 3-card support for two of the three higher-ranking suits. The percentage is 66% that Hearts or Spades can be the second suit, and both being Major suits the score, if correct, would be higher than with a Minor suit fit. 3 The strong Club bidder competes with the second suit of Clubs in the hope of targeting partner or forcing a preference bid. 3 The D.O.N.T. -style overcaller rebids the second suit on the three level. Partner passes knowing that a 9-card fit exists, but that there is no chance of game with the distribution.
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.
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