Low dose superficial x-irradiation to the incisional site after surgical excision of a keloid prevented keloid or hypertrophic scar formation in 31 of 35 patients evaluated (88%). The clinical manifestation of keloids, physiology of wound healing, pathophysiology of keloid formation, and the radiation technique utilized are presented. This study shows that the method is well tolerated, easily administered, and efficient in inhibiting recurrence of keloid or hypertrophic scar formation.