Emergency psychiatry is the clinical application of psychiatry in emergency setting. Conditions requiring psychiatric interventions may include suicide, substance abuse, depression, psychosis, violence or other rapid changes in behavior. Psychiatric emergency services are rendered by professionals in the fields of medicine, nursing, psychology and social work. The demand for emergency psychiatric services has rapidly increased throughout the world since the 1960s, especially in urban areas. Care for patients in situations involving emergency psychiatry is complex. Individuals may arrive in psychiatric emergency service settings through their own voluntary request, a referral from another health professional, or through involuntary commitment. Care of patients requiring psychiatric intervention usually encompasses crisis stabilization of many serious and potentially life-threatening conditions which could include acute or chronic mental disorders or symptoms similar to those conditions.