This volume represents the first attempt to present in one place the clinical syndromes and the pathophysiologic basis for the "resistance states" to each of the classes of steroid hormones. Glucocorticoids, mineralocorticoids, androgens, estrogens, progesterone and vitamin D have widely diverse roles ranging from the control of homeostasis to reproduction and bone formation. They are similar in that they share a chemical structure and that their action is in the cell nucleus where they induce transcription of specific genes leading to synthesis of function-specific proteins. Clinical syndromes of steroid hormone resistance to androgens (complete and partial testicular feminization), aldosterone (pseudo hypoaldosteronism) and vitamin D (vitamin D-dependent rickets type II) have been known for many years. Progesterone and glucocorticoid resistance syndromes have been described only recently. Resistance to estrogens has not been reported in man or in animals. It is hoped that a detailed reexamination of what is known about each of these conditions at the clinical and molecular levels will enhance our understanding of the function of these hormones and their mechanisms of action. New insight and research initiatives should result. G.P. Chrousos D.L. Loriaus M.B. Lipsett vii ACKNOWLEDGMENTS The contents of this volume are based in part on the proceedings of an International Conference held in Bethesda in the summer of 1984. This conference was sponsored by the National Institute of Child Health and Human Development, Bethesda, Maryland.