This clinical guideline on alcohol-use disorders was commissioned by NICE and developed by the National Collaborating Centre for Mental Health, and sets out the evidence for the treatment and management of harmful drinking and alcohol dependence in adults and in young people aged 10 to 17 years. Harmful drinking leads to 2.5 million deaths annually and alcohol is the third leading risk factor globally for burden of illness. Alcohol-use disorders are an increasing problem in children and young people. Physical and psychiatric comorbidities add to the considerable burden that alcohol-use disorders can pose to the individual and to society. This guideline will enable healthcare professionals to recognise and manage these prevalent problems and offer effective treatments to their patients. This guideline reviews the evidence for the diagnosis and assessment of alcohol-use disorders, organisation and delivery of care, settings for assisted alcohol withdrawal, psychological interventions, and pharmacological interventions for assisted withdrawal and relapse prevention. The guideline also includes health economic modelling of pharmacological interventions as an adjunctive treatment for the prevention of relapse and a chapter on the experience of care.