Prolonged grief disorder is a mental health disorder recently included in diagnostic manuals worldwide. This Review presents published research evidence in strong support for the current conceptualisation of prolonged grief disorder: a diagnosable mental health condition with core symptoms of yearning, preoccupation, or both, which is associated with symptoms of emotional pain, identity disturbances, loss of meaning and purpose, and functional impairment. The public and academic discourse surrounding prolonged grief disorder has catalysed researchers to produce methodologically rigorous research evidence in support of this much-needed diagnosis. A coherent syndrome of prolonged grief disorder has a typical onset of 6 to 12 months after the death of a close person. Prolonged grief disorder is associated with various poor outcomes, including negative health outcomes (eg, high blood pressure), increased rates of suicidality, low life satisfaction, and increased service use. Psychotherapy is the main treatment for prolonged grief disorder. Theoretical models of the cause and maintenance of prolonged grief disorder are presently being refined through the rapidly increasing empirical literature. Awareness of prolonged grief disorder by general health practitioners, as well as mental health specialists, is key to appropriate early intervention.
