The high prevalence of mental illness and substance abuse disorders and their significant impact on disability, mortality, and other chronic diseases have encouraged new initiatives in mental health policy including important provisions of the Affordable Care Act and changes in Medicaid. This article examines the development and status of the behavioral health services system, gaps in access to and quality of care, and the challenges to implementing aspirations for improved behavioral and related medical services. Although many more people than ever before are receiving behavioral health services in the United States—predominantly pharmaceutical treatments—care is poorly allocated and rarely meets evidence-based standards, particularly in the primary care sector. Ideologies, finances, and pharmaceutical marketing have shaped the provision of services more than treatment advances or guidance from a growing evidence base. Among the many challenges to overcome are organizational and financial realignments and improved training of primary care physicians and the behavioral health workforce.