Integrated Treatment for Co-Occurring Disorders

Integrated Treatment for Co-Occurring Disorders is an Evidence-Based Practice which addresses a person’s mental health and substance use problems in an integrated way using a long-term, staged approach to recovery. Stages of treatment include engagement, persuasion, active treatment, and relapse prevention. This practice is sometimes called Integrated Dual Disorders Treatment.

Problem or Challenge:

Among people with mental illnesses, co-occurring substance use is common. About half of all people with serious mental illnesses also have substance use disorders. Among people experiencing homelessness, particularly among those who experience chronic homelessness, many people have both substance use problems and mental illnesses. Co-occurring disorders occur at lower rates among other groups of people experiencing homelessness, including families, youth, Veterans, ex-offenders, and others. Mental health and/or substance use problems may be less severe for some of the people in these other groups.

Compared to people with only one diagnosis, people who have co-occurring disorders are at greater risk of homelessness, relapse, hospitalization, incarceration, exposure to violence, and serious infections such as HIV and hepatitis or other health conditions. People with co-occurring disorders find it difficult to navigate fragmented systems of care and programs, which often fail to respond effectively to their complex needs. They may be excluded from services or asked to leave programs because of their co-occurring disorders and told to return when the “other problem” (substance use in a mental health program or mental illness in a substance use treatment program) is “under control.” 


Integrated Treatment for Co-Occurring Disorders has been recognized as an Evidence-Based Practice by the Substance Abuse and Mental Health Services Administration (SAMHSA). Integrated Treatment combines interventions that address a person’s mental illness and substance use problems. Effective programs include a comprehensive, long-term, staged approach to recovery. Recovery means that people are learning how to move beyond illness so they can pursue a personally meaningful life. Integrated treatment supports and empowers consumers to define and achieve their individual goals. These programs recognize that the stages of treatment include:

  • Engagement: forming a trusting relationship
  • Persuasion: helping a person develop the motivation to participate in recovery-oriented interventions
  • Active treatment: helping a person gain skills and supports for controlling mental illnesses and substance use and pursuing goals
  • Relapse prevention: helping a person develop and use strategies for maintaining recovery

Clients do not move along a linear path through these stages and they often relapse or return to an earlier stage. People may be at different stages of change with respect to their mental illness and their substance use disorder. Integrated treatment programs recognize this and use flexible approaches that can be adapted to the needs of individuals at different stages. Services are client-driven and based on unconditional respect and compassion for each individual. Programs take a long-term perspective recognizing that hope is critical and recovery happens over a period of months and years.

Effective programs that demonstrate good outcomes nearly always include all or most of these elements, which make up a core set of practices:

  • Assertive outreach, which may include help with housing and addressing other basic needs before requiring participation in treatment
  • Motivational interventions at all stages, especially at the persuasion stage
  • Assessments that screen for both mental illness and substance use disorders
  • Treatment services for substance use and mental illness are integrated, meaning they are delivered by the same service provider or team, available at the same time and place, and using the same plan with a consistent message about treatment and recovery
  • Service providers or teams have knowledge of both substance use disorders and mental illnesses and understand the complexity of interactions between disorders and medications and substances
  • Multiple formats for services, including individual and group counseling, self-help, and family interventions to promote cognitive and behavioral skills
  • Helping clients to strengthen social supports, build skills, manage both mental illnesses and substance use disorders, and pursue functional goals
  • Flexibility, meaning that different services are provided at different stages and adapted to client goals
  • Medication services integrated and coordinated with psychosocial services
  • Cultural sensitivity and competence

Implementation Steps/Tips:

While Integrated Treatment is highly effective when implemented well, it is often not easy to do. Successful implementation can overcome barriers, using strategies that include:

  • Clarity of program mission with a shared vision for integrated services to guide planning and implementation and shared understanding about priority populations and outcome goals
  • Structural changes to support integrated treatment and recovery support services through collaborative, multi-disciplinary team models, or other approaches that can deliver the right combination of services when and where they are accessible to people with complex needs
  • Training and clinical supervision to help all staff members gain, practice, and get reinforcement for new skills and changes in practice
  • Changes in policies, financing, and organization including integration or alignment of separate government agencies, licensing or certification requirements and systems, eligibility criteria, funding streams, administrative requirements and incentives, information systems, and advocacy organizations
  • Effective communications with consumers, family members and other stakeholders 


The practice ofIntegrated Treatment for Co-Occurring Disorders has been developed, refined, tested, evaluated, and widely replicated over the past three decades (since the 1980’s). Studies have found positive outcomes that include improvements in housing stability, psychiatric symptoms, functional status, and quality of life, and reductions in arrests, hospitalizations, and substance use problems. Programs that show high fidelity, meaning that they include all of the key elements briefly described here, produce better outcomes than low-fidelity programs.


Integrated Treatment for Co-Occurring Disorders Evidence-Based Practices (EBP) KIT is available from SAMHSA (free) in download PDF or CD-ROM /DVD versions. The EBP KIT contains several booklets, presentations, brochures, and other tools that focus on different aspects of the practice and are designed to reach different target audiences (including front line staff and consumers).

The EBP KIT contains a booklet that provides background about the evidence based practice and information about how to successfully implement and sustain programs.

The EBP KIT also contains a booklet that provides more information about the evidence from research literature as well as citations and references to additional resources.

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