In 102 patients referred to our colposcopy clinic because of one to three Papanicolaou smears indicating cervical intraepithelial neoplasia (CIN) and/or abnormal colposcopy, routine smears and colposcopically directed punch biopsies were taken simultaneously. For detection and typing of human papillomavirus (HPV)-DNA in situ hybridization was performed in all biopsies and in 46 of the cervical smears. In cases of dysplastic lesions the number of HPV 16/18 (40.5%) and 31/33 (42.9%) was markedly higher than HPV 6/11 (16.6%) infection rate. In cases where simultaneous in situ hybridization in biopsy specimen and cervical smears was performed 21.7% showed a HPV negative smear and a positive biopsy, in 6.5% the results were the other way round. In 34.9% of cases with CIN I and 9.5% of cases with CIN II verified by punch biopsy the cytological smear did not indicate dysplasia. Our data show that mild and moderate CIN lesions of the cervix as well as HPV infection are detected more frequently by a combination of cervical smear and colposcopically directed punch biopsy than by cervical smear alone.