The National Adult Tobacco Survey of Cambodia 2011 (NATSC, 2011) is the largest national survey of adult tobacco use (age 15 years and older) ever conducted in Cambodia and was completed in January 2011 by the National Institute of Statistic (Ministry of Planning, Cambodia) with support and technical assistance given by the WHO Cambodia, Fogarty International Center and the Southeast Asia Tobacco Control Alliance.  The survey was designed to be comparable to a similar effort in 2005-2006 but also included a comprehensive set of items on tobacco use, cessation, second hand smoke, economics, media and “knoledge, attitudes, and perceptions” from the Global Adult Tobacco Survey GATS).