The prevalence of overweight among US children and adolescents increased between 1980 and 2004. In analyses of national data, Ogden and colleagues Article estimated the 2003-2006 prevalence of high body mass index (BMI) for age at or above the 97th, the 95th, or the 85th percentiles of standard BMI-for-age growth charts. The authors report that 11.3% (95% confidence interval [CI], 9.7%-12.9%) of children and adolescents aged 2 through 19 years were at or above the 97th percentile, 16.3% (95% CI, 14.5%-18.1%) were at or above the 95th percentile, and 31.9% (95% CI, 29.4%-34.4%) were at or above the 85th percentile of BMI for age. The authors found no statistically significant trends in BMI for age between 1999 and 2006. In an editorial, Ebbeling and Ludwig Article discuss pediatric obesity and the clinical use of BMI-for-age categories for risk assessment and patient counseling.