Mental disorders are often diagnosed in accordance with criteria listed in diagnostic manuals such as the widely used Diagnostic and Statistical Manual of Mental Disorders (DSM), published by the American Psychiatric Association, and the International Classification of Diseases (ICD), edited and used by the World Health Organization. The fifth edition of the DSM (DSM-5) was published in 2013, and its development was expected to be of significant interest to many medical fields.

The combined treatment of psychiatric medication and psychotherapy has become the most common mode of psychiatric treatment in current practice, but current practice also includes widely ranging variety of other modalities. Treatment may be delivered on an inpatient or outpatient basis, depending on the severity of functional impairment or on other aspects of the disorder in question. Research and treatment within psychiatry, as a whole, are conducted on an interdisciplinary basis, sourcing an array of sub-specialties and theoretical approaches.