From 1978 to 1982, 49 patients with intraepithelial neoplasia in the vulvar region were included in a prospective investigation. The main purpose was to evaluate the effect of treatment by local excision with a free margin of 2 mm and to estimate the importance of colposcopy. In 28% of the patients, the disease recurred after primary treatment, and in one patient microinvasion was shown. No patients died of cancer. A risk factor of recurrence was involvement of resection margins. Multicentric localization of the vulvar disease was found more frequently among patients treated for intraepithelial neoplasia of the cervix. In 66% of the patients the colposcopic findings were consistent with intraepithelial neoplasia. Local excision represents an improvement in the treatment of intraepithelial neoplasia of the vulva, but frequent follow-up is necessary.