Laser vaporization was used to treat 27 women diagnosed at the Tom Baker Cancer Centre, Calgary, Alberta, Canada, as having vaginal intraepithelial neoplasia. The diagnosis was established after review of vaginal cytologic examination and a histologic biopsy. Treatment was performed with a carbon dioxide laser unit attached to an operating microscope. All but three patients had general anesthesia for the purpose of treatment. Tissue destruction was accomplished to a depth of 2 to 3 mm. Patients were followed up for an average of 14.4 months with regular colposcopy, cytologic evaluation, and biopsy when persistent or recurrent disease was suspected. Failure of therapy was defined as evidence of intraepithelial neoplasia in any one of these three parameters. Four patients required a second treatment. After one or two treatments the success rate of therapy was 78%. In our institution, laser vaporization with the patient under general anesthesia on an outpatient basis is the treatment of choice for vaginal intraepithelial neoplasia.