Between 1984 and 1992, the CO2 laser was used to treat 341 patients affected by CIN of various degrees. On the basis of specific indications these patients underwent vaporization or conization. Two hundred and twenty eight patients underwent vaporization of intraepithelial lesions, 221 (96.92%) of whom were free of disease after one laser treatment, as observed during the subsequent years of follow-up. In 105 out of the 113 patients treated with conization the cone margin was free of disease. One hundred and one (96.19%) of the these 105 patients had no evidence of disease after one year of follow-up. In the remaining 8 (7.07%) cases examination of the cone revealed the presence of invasive carcinoma. The major complication was vaginal discharge observed in 115 (33.72%) patients. The CO2 laser is a very effective therapeutic procedure for the treatment of intraepithelial lesions of the cervix and permits to preserve reproductive function and anatomic integrity.