Sudden death in young competitive athletes is most commonly due to underlying cardiovascular disease. Echocardiography has the potential to identify structural cardiovascular abnormalities, such as hypertrophic cardiomyopathy (HC), that have been incriminated in such events. In this study, echocardiography (2-dimensional and M-mode) was used as a primary screening test to assess 265 Howard University collegiate athletes for cardiovascular disease; 262 (99%) were black. Most athletes (234, 88%) had no definitive echocardiographic evidence of HC or other major cardiovascular diseases, but 30 (11%) had mitral valve prolapse, and 1 other athlete had a small atrial septal defect. In addition, 4 athletes were identified as having mild systemic hypertension. Most athletes (236 of 265) showed normal left ventricular wall thickness of less than or equal to 12 mm, but an important minority (29, 11%) had maximal ventricular septal thicknesses of greater than or equal to 13 mm that could not always be distinguished (by morphology alone) from mild anatomic expressions of nonobstructive HC. Based on this experience, preparticipation athletic screening using echocardiography as the primary test does not appear to be justified on a cost-effective basis. In addition, the substantial minority of subjects with increased wall thickness made clinical interpretation of the echocardiographic findings difficult in individual athletes.