DESCRIPTION: New U.S. Preventive Services Task Force (USPSTF) recommendations about behavioral counseling of adolescents and adults to prevent sexually transmitted infections (STIs). METHODS: The USPSTF reviewed the evidence on the benefits and harms of counseling. The review included studies evaluating behavioral counseling interventions conducted in primary settings, those judged feasible in primary care, and those to which patients might be referred from primary care. RECOMMENDATIONS: The USPSTF recommends high-intensity behavioral counseling for all sexually active adolescents and for adults at increased risk for STIs. (B recommendation) Current evidence is insufficient to assess the balance of benefits and harms of behavioral counseling to prevent STIs in non-sexually active adolescents and in adults not at increased risk for STIs. (I statement).