The time of onset and progression of pubertal development has been documented in seven male patients with Addison's disease. Two patients developed associated autoimmune problems before puberty and were excluded from further study. The mean age of the onset of puberty among the remaining five patients was 12.3 ± 0.4 yr, not different than the 11.4 ± 0.4 yr reported for normal American boys. Integrated plasma levels of testosterone, androstenedione, 17-hydroxyprogesterone, progesterone, and dehydroepiandrosterone were also determined in three Addisonian patients who had no associated autoimmune diseases before puberty and their study date. Results were compared with integrated plasma levels from three other groups: four agonadal males, four normal adult males, and three pubertal boys. Integrated plasma levels of these steroids confirm that in a male, testosterone is essentially testicular in origin, dehydroepiandrosterone is mainly adrenal in origin, and androstenedione and 17-hydroxyprogesterone are derived from both sources.