Major medical illnesses remain undiagnosed and patients' ailments are being labeled "psychosomatic" at an alarming rate. A careful screening of 2,090 psychiatric clinic patients showed that 43% of this population suffered from one or several physical illnesses. Almost half of the physical illnesses (46%), remained undiagnosed by the referring source. Morbidity in the psychiatric clinic patients far surpassed the expected rate found in the general population. Among others, diabetes mellitus was a frequently overlooked diagnosis and proved, particularly, to produce emotional disturbances. Physicians other than psychiatrists missed one third and psychiatrists one half of the major medical illnesses in patients they referred. Self-referred and social agency--referred patients almost always had undiagnosed physical illnesses. The causes for failing to recognize medical illnesses are discussed. Based on the obtained data, the necessity for a medical orientation on the part of psychiatrist in evaluating all patients is stressed.