This conventional defense method was devised and developed by Mr. Alvin Leon Roth of Boca Raton, Florida, United States. He was also the co-author of the Roth-Stone System. Mr. Alvin Roth developed or co-developed many bridge conventional methods, which were considered by his peers as avant garde.

Biographical Data

Mr. Alvin Leon Roth was born on November 6, 1914, in New York, United States, and died April 18, 2007. He was regarded as one of the greater bridge personalities of his era. He authored several publications and also devised various bridge conventional methods such as negative doubles, the Forcing No Trump, and the Unusual No Trump. He relocated to Miami Beach, Florida, United States, and founded the Charles Goren School of Bridge.

Mr. Alvin Leon Roth was a Grand Life Master of the American Contract Bridge League, elected to the ACBL Hall of Fame in the year 1995, and he was also a World Life Master of the World Bridge Federation.


Principles of the Concept

This particular conventional defense method, employed after an opening of No Trump by an opponent, allows the intervenor to show weak, but distribution holdings with a 5-5 distributional pattern. The defense method also includes the possibility of showing a one-suited holding in either Major suit, but not a Minor two-suited holding.

Whether or not this conventional defense method is applicable after two consecutive passes in the balancing seat is a matter of partnership agreement.

The following bids show the meanings of the overcalls. Source: bcmcIV.

Double: Any double is artificial and promises a two-suited holding in both Major suits.
2 : Promises a black two-suited holding with Clubs and Spades.
2 : Promises both pointed suits, Diamonds and Spades.
2 : Natural. Promises a minimum of a 6-card Heart suit.
2 : Natural. Promises a minimum of a 6-card Spade suit.
2 NT: An artificial bid promising a 4-card plus Heart suit in addition to an unspecified 6-card Minor suit.
3 : Promises both rounded suits, Clubs and Hearts.
3 : Promises both red suits, Diamonds and Hearts.

The point count is relevant in that the majority of the trick-taking values are in the promised suit or suits, in order that the overcall proves effective. The distributional strength holds more validity and importance than the amount of the points. However, the state of the vulnerability plays an important role in determining whether or not to overcall. If the chance of a double would probably result in a better score for the opponents, then a pass is recommended.


All continuances by the advancer are based on partnership agreement. This principle also applies if the partner of the No Trump bidder competes after the overcall. However, since all suits are known to the advancer, the principle of preference would be in effect, meaning that the advancer would know which suit or suits are meant and bid accordingly. In order to discover the unspecified Minor suit after an overcall of 2 No Trump, the advancer would relay to 2 Clubs and the intervenor would either pass or correct.



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.