The degree to which mental health services and coverage have been integrated into prepaid health plans (PHPs) on a national level is unknown. Using two self-administered mail questionnaires, the authors obtained descriptive data on the organization and delivery of mental health services within 205 PHPs throughout the United States and Guam. After discussing the growth of PHPs in the United States and the development of prepaid mental health services, the authors analyze the survey data using the PHP as the unit of analysis. Although 94 percent of the PHPs in the survey offered mental health benefits as part of their basic health plan, the authors found that the varied organizational characteristics of both the PHPs and their mental health components may have affected the specific mental health services provided as well as their costs, utilization, and referral patterns. The authors believe that further analysis of the various PHP organizational models is necessary to understand the utilization and costs of prepaid mental health services.