As part of a large, multicenter trial, 82 patients with endometriosis were randomized to 6 months of treatment with either nafarelin or danazol. Among 73 patients who had subjective symptoms (dysmenorrhea, dyspareunia, or pelvic pain) at baseline, 94% of patients treated with nafarelin and 91% of those treated with danazol had improvement. Resolution of physical findings also was observed in similar percentages of patients in each treatment group. Long-term studies are needed to determine whether these two agents are associated with different cure rates or times to recurrence of disease. © 1990.