Its some 37,800 members are mainly American but some are international. The association publishes various journals and pamphlets, as well as the Diagnostic and Statistical Manual of Mental Disorders (DSM). The DSM codifies psychiatric conditions and is used worldwide as a guide for diagnosing disorders.
The organization has its headquarters in Washington, D.C.
At a meeting in 1844 in Philadelphia, thirteen superintendents and organizers of insane asylums and hospitals formed the Association of Medical Superintendents of American Institutions for the Insane (AMSAII). The group included Thomas Kirkbride, creator of the asylum model which was used throughout the United States. The group was chartered to focus "primarily on the administration of hospitals and how that affected the care of patients", as opposed to conducting research or promoting the profession.
In 1893, the organization changed its name to The American Medico-Psychological Association. In 1921, the Association changed that name to the present American Psychiatric Association. The Association was incorporated in 1927.
The cover of the publication Semi-Centennial Proceedings of the American Medical Psychological Association, which the Association distributed in 1894 at its 50th annual meeting in Philadelphia, contained the first depiction of the Association's official seal. The seal has undergone several changes since that time.
The present seal is a round medallion with a purported likeness of Benjamin Rush's profile and 13 stars over his head to represent the 13 founders of the organization. The outer ring contains the words "American Psychiatric Association 1844." Rush's name and an M.D. are below the picture.
According to wikipedia