The increasing prevalence of childhood overweight/obesity and their associated morbidities are well established, yet rates of diagnosis and screening for related conditions by clinicians are low. Expert Committee recommendations were released in 2007 to facilitate management of pediatric overweight/obesity. From well-child visits to a Massachusetts multisite group practice, we randomly selected 1 visit per child in 2006 (n = 56 374) and in 2008 (n = 69 681) and used electronic health record data to identify children with incident overweight or obesity (BMI ≥ 85th percentile) and ascertained whether clinicians assigned relevant ICD-9 (International Classification of Diseases, Ninth Revision) codes and ordered laboratory tests recommended for children ≥10 years old. In the year following the release of recommendations, a large majority of children 2 to 17 years old with a BMI ≥85th percentile lack diagnosis codes for overweight/obesity and recommended laboratory orders for assessment of obesity-related comorbidities for children 10 years and older, suggesting the need to augment current approaches to increase uptake of guidelines.