Suicide is a major global challenge with an estimated 700 000 people taking their lives each year. Each of these deaths is an individual tragedy affecting families, friends, communities and health and social care teams. As clinicians and researchers working in suicide prevention, we are sometimes contacted by people whose loved ones have died by suicide while under the care of mental health services. Although we hear about examples of high-quality care, there are also accounts of poor continuity, failed communication, diagnostic or therapeutic errors, poorly trained or resourced clinical teams or a lack of family involvement. Suicide is a complex phenomenon and many of its drivers are economic and social, but its prevention should be a priority for health services in general and for mental health services in particular. Specifically, mental health patients represent a group at greatly elevated risk of suicide who are accessible because they are in contact with services.