Objective: In Slovenia the opportunistic cervical cancer (CC)screening programme has been performed within the regular gynaecological practice since 1960. The incidence rate 28.8/105 decreased to 16.1/105 in 1982, and increased to 23/105 in 1996. To explain the increased CC incidence the patientsscreening histories, occurrence of symptoms, and details of preventive measures were studied on the basis of medical records and questionnaire. Errors of cytological screening were analysed by reviewing previous smears. Material: The answers obtained from 324 women, treated for CC in the period 1995-2000, were analysed in relation to age, stage and histology. The mean womens age was 46.76 ±13.07 (S.D.) years (range 23-85 years). After therapy, 271 patients were followedup by the end of January 2004, (mean followup time 80.3 ±20 S.D. months, range 29.7-110.3 months). Statistical analysis was performed using Chisquare test. Results: In 208 (80%) cases, CC was detected in stage 1, in 43 (17%) in stages 2A to 3B. Squamouscell carcinoma (192, 74.1%) was followed by adenocarcinoma (61, 23.5%) and (5, 1.9%) other malignancies. The screening interval ranged from 6 months to 4 years. Statistically significant differences existed between clinical and screening variables. CC was diagnosed in higher stages in women who were ignorant of the Pap test. Rescreened smears (n=126) showed 27.8%of false negative results. Conclusions: The reasons for high incidence of CC are poor performance of cytological screening, failures in gynecological examinations and diagnostic procedures, and the patientsnegligence of attending regular screening. Objective: In Slovenia the opportunistic cervical cancer (CC) screening program has been performed within the regular gynecological practice since 1960. The incidence rate 28.8 / 105 decreased to 16.1 / 105 in 1982, and increased to 23/105 in 1996. To explain the increased CC incidence the patients’screening histories, occurrence of symptoms, and details of preventive measures were studied on the basis of medical records and questionnaire. Errors of cytological screening were analyed by reviewing previous smears. treated for CC in the period 1995-2000, were analyzed in relation to age, stage and histology. The mean women’s age was 46.76 ± 13.07 (SD) years (range 23-85 years). After therapy, 271 patients were followed Upup by the end of January 2004, (mean followup time 80.3 ± 20 SD months, range 29.7-110.3 months). Statistical analysis was performed using Chisquare test. Results: In 208 (80%) cases, CC was detected in stage 1, in 43 (17%) in stages 2A to 3B. Squamous cell carcinoma (192, 74.1%) was followed by adenocarcinoma (61, 23.5%) and Statistically significant differences existed between clinical and screening variables. CC was diagnosed in higher stages in women who were ignorant of the Pap test. Re-screened smears (n = 126) showed 27.8% of false negative results. Conclusions: The reasons for high incidence of CC are poor performance of cytological screening, failures in gynecological examinations and diagnostic procedures, and the patients negligence of attending regular screening.