As the use of drugs and alcohol by clients accessing mental health services becomes increasingly common, members of staff working within psychiatric inpatient areas often encounter drug and alcohol misuse among their client group. The safe and effective management of this issue has become a priority for many inpatient services. This paper outlines a policy for the management of substance misuse on psychiatric inpatient wards developed by Manchester Mental Health and Social Care Trust. The fundamental principles underpinning the policy are highlighted, and the key sections of the policy are described. There is a detailed description of how the policy has been applied in practice by members of staff working on inpatient wards, with clinical examples being presented.