Substance use and addiction is an increasing problem amongst older people. The identification of this problem is often more difficult in older patients and is frequently missed, particularly in the primary care context and in emergency departments, but also in a range of medical and psychiatric specialties. Substance use and older people shows how to recognize and treat substance problems in older patients. However, it goes well beyond assessment and diagnosis by incorporating up-to-date evidence on the management of those older people who are presenting with chronic complex disorders, which result from the problematic use of alcohol, inappropriately prescribed or over-the-counter medications, tobacco or other drugs.