BACKGROUND Several studies have examined the agreement between Papanicolaou smear cytology and subsequent biopsy results in the diagnosis of cervical dysplasia. However, few studies have focused specifically on koilocytotic (KC) atypia. Given the increasing frequency of reporting KC atypia on Papanicolaou smears, we sought to obtain more information on the relationship between Papanicolaou smears and subsequent colposcopically directed cervical biopsies. METHODS Retrospectively, we compared the Papanicolaou smears and colposcopically guided biopsy results for 132 college women who had abnormal Papanicolaou smears (KC, cervical intraepithelial neoplasia [CIN], or reactive atypia [RA]). Data were compiled through systematic review of the charts of these women. The cervical biopsies were taken 6 months or less after the Papanicolaou smears. RESULTS Of 99 women having only KC atypia on cytology, histology revealed concordance in 51 cases and underlying dysplasia in 16 cases. Only one biopsy revealed CIN III, and no biopsies showed invasive carcinoma. We also noted variation in the histologic results between the laboratories that analyzed the biopsy specimens. In comparing the biopsy results after one or two KC atypic Papanicolaou smears 6 months or less apart, we found no statistically significant difference. CONCLUSIONS These findings suggest that physicians who obtain an initial Papanicolaou smear read as KC atypia could obtain a second smear 3 months later to determine if there is persistent KC atypia before advising a patient to have cervical biopsy. In addition, physicians also should know the limitations of the laboratories providing them with information.