The purpose of this study was to assess the effectiveness of behavioral counseling interventions in reducing sexual risk behaviors and HIV/STI prevalence in low- and middle-income countries. A systematic review of papers published between 1990 and 2011 was conducted, identifying studies that utilized either a multi-arm or pre-post design and presented post-intervention data. Standardized methods of searching and data abstraction were used, and 30 studies met inclusion criteria. Results are summarized by intervention groups: (a) people living with HIV; (b) people who use drugs and alcohol; (c) serodiscordant couples; (d) key populations for HIV prevention; and (e) people at low to moderate HIV risk. Evidence for the effectiveness of behavioral counseling was mixed, with more rigorously designed studies often showing modest or no effects. Recommendations about the use of behavioral counseling in developing countries are made based on study results and in light of the field's movement towards combination prevention programs.