Brief Integrated Motivational Intervention provides clinicians and specialist practitioners with a brief, evidence-based treatment approach for motivating clients, who have comorbid mental health and alcohol and drug misuse. Developed by an expert team, with many years of research and practice experience in the fields of psychosis and addiction, this approach combines cognitive behavioural therapy (CBT), motivational interviewing, and the authors' own cognitive-behavioural integrated treatment (C-BIT). It allows practitioners to engage clients in meaningful dialogue for change during short windows of opportunity following relapses or admittance to psychiatric hospital, and helps clients consider the impact of substance misuse on their mental health. Easy to understand and implement, this guide also includes helpful tools for practitioners, such as session-specific content, illustrative case material, easy-to-use worksheets, and additional information for family members and friends.