The ninth edition of the Laws of Duplicate Bridge comes into force tomorrow.

THE new Laws of Duplicate Bridge, which came into force on April 1, have no impact on social players.

The start tomorrow in North America of the revised "Laws of Duplicate Bridge" is the result of years of effort by international committees.

The revised "Laws of Duplicate Bridge," which come into force today in North America, will be a shock for some, particularly those who were social players before they became duplicate enthusiasts.

The strong pass is already barred in many parts of the world, and the new Laws of Duplicate Bridge, due to come into force in this country on March 31, have been written to permit the restriction.

The official rules of duplicate bridge are promulgated by the World Bridge Federation (WBF) as the "International Code of Laws of Duplicate Bridge, 2007".

The most relevant change is Law 16C2 (Law 16D2 in the 2007 Laws Of Duplicate Bridge), which defines information gained from either side's legal withdrawal of a card as unauthorized for the offending side.

For example, the American Contract Bridge League publishes "Laws of Duplicate Bridge, 2008", "Laws of Contract Bridge, 2003" and additional supporting documentation including: Director Decisions, Tech Files and Casebook (appeals from national bridge championships).

Besides the Bridge Bulletin, other ACBL publications include the Laws of Duplicate Bridge (named Laws of Duplicate Contract Bridge until 2008), the ACBL Bridge Series of lessons for beginners, and free instructional software.