Strong pass

In the card game of bridge, a strong pass is an opening pass that indicates a strong hand, typically with a minimum of 11-16 points. Strong pass bidding systems are of a quite different nature from the more typical "natural" systems, but share some similarities with strong club systems. Strong pass systems are sometimes called "forcing pass" systems; the term "strong pass" is preferred here to avoid confusion with a different meaning of the term "forcing pass" in bridge.

Since "pass" is used to indicate strong hands, weaker hands—even those with no points—must make an opening bid. Typically, one bid is used for extremely weak hands (less than 8 or 9 points); this is called a "fert" bid (short for fertilizer, as it is used when your hand is a load of manure). All other bids show limited-strength hands of various distributions. The fert bid is usually between 1♣ and 1♠; higher bids are more preemptive, but correspondingly more dangerous. Because of the necessity of using a fert bid, the limited openings usually have a significantly lower range than in strong-club systems, and very weak preemptive bids on the 2 and 3 levels are allowed.

The basic motivation of strong pass systems is to reserve as much bidding room as possible for strong hands, and to be as preemptive as is safely possible with weak hands. Strong pass systems are often coupled with relay systems for precisely describing strong hands, and limited bids are heavily oriented towards finding low-level major-suit contracts, with "major-suit" bids (i.e. bids that promise a certain major-suit holding, which are not necessarily natural heart or spade bids — most strong-pass systems are highly artificial) typically promising only four cards in a particular major.

Note that a strong-pass partnership will always open the bidding when playing first position, or when second position after an opposing natural pass. Thus, partnerships playing against a strong pass system will be on defense much more often than normal, and must have highly developed defensive methods for handling situations where the partnership possesses game strength or more. As a result, strong-pass systems are typically prohibited at all but the highest levels of tournament play.

A sample strong-pass system is the TresBoof system. The outline of the opening bids of this system is as follows, with relative frequencies attached:

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