American Psychiatric Association : Diagnostic and Statistical Manual of Mental Disorders - DSM-I

The American Psychiatric Association (APA) is the main professional organization of psychiatrists and trainee psychiatrists in the United States, and the most influential world-wide. The association publishes various journals and pamphlets, as well as the Diagnostic and Statistical Manual of Mental Disorders, or DSM. The DSM codifies psychiatric conditions and is used world-wide as a key guide to diagnosing disorders.