The principle of the "Multi" - the idea that one bid can encompass a variety of different meanings - has a well-established history. In the modern game, the Multi Two Diamonds is one of its most popular applications. If you adopt the Multi, you have now opened up interesting alternative uses for as many as three other two-level openings. This book is a first comprehensive look at Multi ideas as they are used today, also covering the Multi Landy (Woolsey) defense to 1NT and defenses against the Multi, making this a valuable book even for those who don't wish to play the convention themselves. The final chapter, entitled "The Multi in Action," consists of a wealth of examples from top-level play.
Mysterious Multi : How to Play it, How to Play Against It