Colposcopy and cervicography are accepted tools for assessing the cervix for an atypical transformation zone. We studied the validity of the colpophotograph as a measurement tool by determining the agreement of experienced colposcopists using colpophotographs of 50 women. Interobserver agreement was generally fair to good (k≥0.40) for the presence of the squamocolumnar junction and the area of ectopia but it was poor (k<0.40) for the area, border, and color characteristics of an atypical transformation zone. Intra-observer agreement was fair to good for the color characteristics of an atypical transformation zone, but it was poor for the area and border characteristics. We conclude that observer agreement studies should play a role in the validation of methods used in the visual diagnosis of cervical intraepithelial neoplasia. Considerable lack of agreement in reporting cytologic findings is a well-known problem, and lack of agreement might be an even bigger problem in reporting colposcopic findings.