Four patients who developed endometriosis at the episiotomy scar are reported. The latent period varied from 6 months to 10 years before the onset of symptoms. Three of them experienced cyclic pain at the site of the lesion during their menses and one patient had bloody discharge from the scar during menstruation. All patients were managed surgically and no one had recurrence during the follow-up period which ranged from 2 to 5 years. The pathogenesis of endometriosis is discussed as a clinical entity; the literature is also reviewed.