The CASPIAN Study aims to implement a school-based surveillance system for prevention of noncommunicable diseases from childhood in the Islamic Republic of Iran. The baseline survey was conducted from November 2003 to May 2004 in 23 provinces among 21 111 school students aged 6–18 years and their parents. The data collected included birth weight and current anthropometric measurements; dietary and exercise habits; family history of chronic diseases; and knowledge about prevention. Fasting blood sugar and lipid profile were assessed in a subsample of 4811 students.