The DSM-IV, the U.S. standard reference for psychiatry, includes over 300 different manifestations of mental illness. Psychiatrists themselves are in dispute over how common some of these conditions are, or whether they should be listed as 'mental illnesses', and each version of the DSM is slightly different to the previous ones. The DSM-IV is currently being revised and updated, and the next version will include new-and-improved manifestations of illness. This is a portion of the currently recognised list of mental illnesses.

See Mental illness for more general information.