The urinary excretion of a 17-hydroxycorticosteroids, pregnanetiol, 17-ketosteroids, 11-deoxy-17-ketosteroids, and testosterone were measured in normal men and men with endocrine disorders before and during four days of chorionic gonadotropin administration. Testosterone excretion at least doubled in all normal men and showed the greatest change. Androsterone and etiocholanolone increased to at least 150% of the control. Patients with hypopituitarism and primary testicular disease could not be consistently differentiated on the basis of their response to gonadotropin. Patients with delayed puberty and hypogonadotropic hypogonadism has variable responses. In patients with acromegaly, baseline steroid excretion and response to gonadotropin did not differ from normal men.