The purpose of this series of volumes is to present a comprehensive view of the complications that result from the use of acceptable diagnostic and therapeutic procedures. Individual volumes will deal with iatrogenic complications involving (1) the alimentary system, (2) the urinary system, (3) the respiratory and cardiac systems, (4) the skeletal system and (5) the pediatric patient. The term iatrogenic, derived from two Greek words, means physician-induced. Originally, it applied only to psychiatric disorders generated in the patient by autosuggestion, based on misinterpretation of the doctor's attitude and com­ ments. As clinically used, it now pertains to the inadvertent side-effects and com­ plications created in the course of diagnosis and treatment. The classic categories of disease have included: (1) congenital and developmental, (2) traumatic, (3) infectious and inflammatory, (4) metabolic, (5) neoplastic, and (6) degenerative. To these must be added, however, iatrogenic disorders-a major, although gen­ erally unacknowledged, source of illness. While great advances in medical care in both diagnosis and therapy have been accomplished in the past few decades, many are at times associated with certain side-effects and risks which may result in distress equal to or greater than the basic condition. Iatrogenic complications, which may be referred to as "diseases of medical progress," have become a new dimension in the causation of human disease.