Evolving U.S. service model for patients with severe mental illness and co-occurring substance use disorder

Co-occurring severe mental illness and substance use disorder has been recognized as a common problem in the U.S. since the early 1980s (1–3). For these individuals with co-occurring disorders, research demonstrates the effectiveness of various forms of combining, blending, or integrating mental health and substance abuse treatments (4). The evolving U.S. service model for integrated dual disorders treatment emphasizes several key elements: implementation, leadership, training, engagement, assessment, counseling for all patients, ancillary treatments for those with multiple needs, secondary treatments for patients who are nonresponders, and quality assurance regarding process and outcomes.