Various views of schizoid personality disorder in descriptive psychiatry, psychoanalysis, DSM-III and DSM-III-R are reviewed and synthesized to develop a composite picture of the syndrome. The disorder is seen as consisting of characteristic deficits in six areas of psychosocial functioning: (1) self-concept, (2) interpersonal relations, (3) social adaptation, (4) ethics, standards and ideals, (5) love and sexuality, and (6) cognitive style. Such a view maintains historical continuity in the use of the term "schizoid," combines descriptive and psychodynamic observations and correlates the behavioral and psychostructural aspects of the schizoid pathology. The paper also identifies guidelines for distinguishing the schizoid personality from other personality disorders as well as areas needing continued research.