This study examines the trends in the prevalence of overweight among WIC children during the 1990s. The study is based on data collected by the biennial WIC Participant and Program Characteristics Studies (1992, 1994, 1996, and 1998). Overweight prevalence among WIC children is measured according to the revised growth charts, released by the National Center for Health Statistics (NCHS) in May 2000.WIC is the Special Supplemental Nutrition Program for Women, Infants, and Children. This Federal program is administered by USDA and provides supplemental foods, nutrition education, and health care referrals to pregnant and postpartum women, infants, and children up to age 5 who are income eligible and at nutritional risk. WIC regulations require anthropometric measurements (height or length, and weight) be taken and recorded as part of determining nutritional risk for all enrollees, and these data are regularly reported in the biennial WIC Participant and Program Characteristics Studies.