This convention is used to put an overcaller on lead. This page explains how it is a jump cue bid in the opponent's overcalled suit.

Explains Mr. Marty Bergen's convention for dealing with an opponents double of your 1NT opening bid.

Explains this convention which allows the responder to convey the exact number of trumps held, and the strength, all in one bid.

Explains this convention used to find out more about opener's hand. Includes examples and variations.

This convention is a type of Sacrifice bid when you expect the opposition to make game in a major suit. It is covered clearly on this page.