The face of many endocrine diseases is rapidly changing as early detection and intervention is achieved. Nevertheless, certain musculoskeletal symptoms can suggest a possible endocrinopathy. The clinician can expect the appearance of particular rheumatic problems during the course of a chronic endocrine disorder. This is especially germaine for diabetes and acromegaly, in which the disorder is controlled but not cured. Clearly hormones play a critical role in the development and expression of immunologic disease. Sex hormones and calcitriol have a direct effect on basic immunobiology (3). The rheumatoid synovium responds to parathyroid hormone and calcitriol in concert with local signals such as prostaglandins, interleukins, and interferon (2,77). Finally, the immune system plays a central role in the pathogenesis of several endocrine diseases. The thyroid diseases, Graves' disease and Hashimoto's disease are best studied. The mechanisms of Ia expression leading to immune destruction and lymphocytic infiltration of the gland will be applied to other endocrine disorders.