OBJECTIVE To compare the ability of combined cytology and cervicography with cytology alone to decrease the number of premalignant cervical lesions found in subsequent screening. METHODS Five thousand five hundred fifty women 18-91 years old were randomized to cytology plus cervicography or cytology alone. One year later, women were rescreened using both cytology and cervicography. All women with positive lesions were referred for colposcopically directed biopsies and treatment as indicated. We expected to decrease by half the number of cervical intraepithelial neoplasia (CIN) lesions at 1-year screening by adding cervicography to cytology at initial screening. RESULTS Compared with cytology screening alone, screening with cytology plus cervicography showed a 30% reduction in CIN I-II-III cervical lesions at 1-year screening round (relative risk [RR] 0.70; 95% confidence interval [CI] 0.32, 1.55, P = .35) and a 43% reduction in CIN II-III cervical lesions (RR 0.57; Cl 0.14, 2.16, P = .36). Most lesions detected by one test were not detected by the other. In a retrospective search, nine biopsies (one normal and eight revealing CIN I or more on histopathology) were found to be positive for the human papillomavirus; five of the nine biopsies were found by cytology, three by cervicography, and one by both tests. CONCLUSIONS The addition of cervicography to cytology in initial screening did not significantly decrease the number of premalignant cervical lesions detected 1 year later, probably because of the transient nature of most of these lesions. Because cytology and cervicography seemed to detect different premalignant lesions, it is possible that cervicography could detect lesions that do not express the cellular abnormalities necessary for detection by cytology.