Objectives: To estimate the frequency of occult depressive symptoms in adolescent emergency department (ED) patients (aged 13-17 years) and to determine patient characteristics associated with depressive symptoms. Design: A cross-sectional study of adolescent ED patients. Setting: The pediatric ED of Hennepin County Medical Center in Minneapolis, Minnesota, and the EDs of the Children's Hospitals and Clinics of Minnesota. Patients: Medically stable adolescent ED patients with nonpsychiatric concerns. Interventions: Patients completed the Beck Depression Inventory II and answered questions about their attitudes, activities, and lifestyle choices. Guardians were asked about family demographics, living situations, and other patient characteristics. Main Outcome Measures: The frequency of moderate and severe depressive symptoms as measured by the Beck Depression Inventory II. Group results were analyzed with descriptive statistics; patient characteristics associated with depressive symptoms were determined by multivariate analysis. Results: A total of 967 patients were enrolled. According to the Beck Depression Inventory II, 20% (197 patients) had moderate to severe depressive symptoms. Of these, 58% recognized their depressive symptoms and 50% were recognized by their guardians as having depressive symptoms. When compared with nondepressed patients, adolescents with depressive symptoms more often were female, were not involved in organized social activities, knew someone who intentionally hurt himself or herself or died a violent death, were currently involved in a sexual relationship, or used street drugs. Race, family income, family stability, and witnessing violence were not associated with a positive depression screen result. Conclusions: Depressive symptoms occur frequently among adolescents and are often unrecognized. Efforts to increase awareness of depression among ED physicians, adolescents, and parents of adolescents may be beneficial.