Weak Opening Systems, or WOS, have become bidding systems in their own right. The first such system was primarily accomplished by Mr. Jukasz Slawinski of Poland. It was based originally upon the concept behind a Strong Two Club bidding system. This concept was revised, expanded, and amended.

The most distinguished difference is that a player must pass with a good hand, called a Forcing Pass, but is forced to open the auction with zero values, such as a Yarborough. This very weak bid, also referred to as FERT because of its relative connotation to fertilizer, normally shows 0-7 high card points.

Holding a point range between 8 and 12 high card points, the partnership must open the auction with different, prior agreed bids. Holding 13 plus high card points, the holder must pass to communicate this information to his partner, who then must bid, by opening the auction or by overcalling.

These Weak Opening Systems are known as dominant systems since they are forcing the opponents more or less into a rather defensive position. It is usual that the opponents apply their personal bidding system only when they deal or are dealer and when one of the opponents is the dealer.

If this is not the case, then the partnership using the Weak Opening Systems dictates the form of the auction. There are many forms of the Weak Opening System, but only three of the original work done by Mr. Jukasz Slawinski of Poland are considered.  

Delta

This form of the Weak Opening System is rather unique in that the opener shows his shortage before he shows his long suit. The advantage to this form is that the responder already has some information regarding the fit of both holdings.

Pass:	Shows 13 plus high card points.
1 :	Shows 9-12 high card points and any hand with no singleton or void.
1 :	Shows 0-7 high card points.
1 :	Shows 8-12 high card points and any hand with a singleton or void in Hearts, or a singleton or void in Clubs, and either a long Major suit or a 5-5 shape.
1 :	Shows 8-12 high card points and any hand with a Spade shortage.
1 NT:	Shows 8-12 high card points with a Diamond shortage and either a long Major suit or a 5-5 shape.
2 :	Shows 8-12 high card points and all other hands with a Diamond shortage.
2 :	Shows 8-12 high card points with a Club shortage and long Diamonds.
2 :	Shows 8-12 high card points and all other hands with a Club shortage.

Some partnerships apply the Delta form of the Weak Opening System with a variation in order to avoid the feature of the Forcing Pass. In this modification, a Pass shows 0-11 high card points, a 1 Diamond bid shows any 17 high card points plus holding, and all other bids are the same as illustrated above but with 12 to 16 high card points instead of 8 to 12 high card points.

Moscito

In this modification of the Weak Opening System, a 1 Diamond opening informed the partner about a 4-4 distribution in both Major suits. An opening of one of the Major suits, either Spades or Hearts, informed the partner that the opener had at least four cards in the mentioned Major suit, less than four cards in the other Major suit, and most likely a longer, unknown Minor suit. A 1 No Trump opening suggested strongly a balanced holding without a 4-card Major suit and a Stayman request therefore inquired about a 3-card Major suit holding.\

No Name

This form of the Weak Opening System shows basically the high card point range as the Delta variation, but the main difference is placed on the importance of the shape and distribution of the holding

Pass:	Shows 13 plus high card points.
1 :	Shows 8-12 high card points with at least 3-3 shape in the Major suits; at most 5-4, but not 5-3 shape.
1 :	Shows 0-7 high card points.
1 :	Shows 8-12 high card pointsH with at most 2 cards or at least 6 cards in the bid suit.
1 :	Shows 8-12 high card points with at most 2 cards or at least 6 cards in the bid suit.
1 NT:	Shows 8-12 high card points with 5 Hearts and 4 Clubs, or 5 Spades and 4 Diamonds.
2 :	Shows 8-12 high card points with 5 Hearts and 4 Diamonds, or 5 Spades and 4 Clubs.
2 :	Shows 8-12 high card points with 5-3-2-2 distribution and either 5-card Major suit.
2 :	Shows 8-12 high card points with at least a 5-5 or at most a 6-4 distribution.
2 :	Shows 8-12 high card points with at least a 5-5 or at most a 6-4 distribution.
2 NT:	Shows 8-12 high card points with at least a 5-5 or at most a 6-4 distribution.
3 :	Shows 8-12 high card points with at least a 5-5 or at most a 6-4 distribution.

Regres

This form of the Weak Opening System shows a different shape and distribution through different bids. Otherwise, it follows basically the same pattern as the other forms and modifications of the Weak Opening System.

Pass:	Shows 13 plus high card points.
1 :	Shows 8-12 high card points and a catch-all opening for any hand not fulfilling any other requirements.
1 :	Shows 0-7 high card points.
1 :	Shows 8-12 high card points with 3 or 4 cards in the bid suit (possible 5-card side Minor suit).
1 :	Shows 8-12 high card points with 3 or 4 cards in the bid suit (possible 5-card side Minor suit).
1 NT:	Shows 8-12 high card points with at least 5 cards in one of the Major suits.
2 :	Shows 8-12 high card points with at least 5 cards in the bid suit and no Major suit.
2 :	Shows 8-12 high card points with at least 5 cards in the bid suit and no Major suit.
2 :	Shows 8-12 high card points with a 5-5 or 6-4 shape and distribution.
2 :	Shows 8-12 high card points with a 5-5 or 6-4 shape and distribution.
2 NT:	Shows 8-12 high card points with a 5-5 or 6-4 shape and distribution.
3 :	Shows 8-12 high card points with a 5-5 or 6-4 shape and distribution.

Once the point range is known to the partner, the auction generally continues on the basis of a relay method, the responder requesting further and additional information regarding the complete shape of the hand of the opener. After this is accomplished, the responder has several choices, and those are either to continue with the relay with Asking Bids or to use the End Signal, which is a bid of 4 Diamonds. This End Signal requests the opener to puppet with the bid of 4 Hearts, and the responder then sets the final contract.

In other modifications of Weak Opening Systems, a feature called the One-Under Opening Bid was used. The opening bid of 1 Diamond, for example, meant that the bidder in truth is bidding 1 Heart, and the opening bid of 1 Heart actually meant the opening bid of 1 Spade, and so on.

There are many forms of the Weak Opening Systems, but all forms have not met with acceptance by the ACBL, the World Bridge Federation and other governing bodies, which regulate the activities and oversee the regulations enacted at tournaments and competitions. The Weak Opening Systems have become therefore unpopular because they are allowed at so few bridge events. The partnerships, which formerly agreed to play them, have agreed to use other bidding systems.

 

 

If you wish to include these features, 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.