Peyronie's disease, a penile deformity of the mature male, is distressing but not necessarily permanent. The initial inflammatory infiltrate does not always progress to irreversible fibrosis. Although spontaneous resolution sometimes occurs, resolution can be hastened and rendered more likely by anti‐inflammatory measures such as cortisone and small‐dose irradiation. Pain may have some significance. The deformity on erection tends to persist when treatment is delayed until pain has developed. The pain itself will often disappear. Fifty‐six patients were given small‐dose irradiation. Forty‐six determinate cases were available for definitive evaluation. Deformity persisted in only 4 of 10 (40 per cent) who were treated before pain had developed. Of the 36 who were treated after the development of pain, the deformity persisted in 24 (67 per cent). The pain failed to respond in only 7 of the 36 (19 per cent). Objective evaluation is difficult. Aggressive intervention may do more harm than good. Properly administered, small‐dose irradiation is an innocuous form of treatment which may prove helpful.