OBJECTIVE To investigate whether the currently recommended age at which to stop cervical screening (64) can be lowered and what criteria should be used for safely doing so. METHODS Retrospective case analysis study. METHODS Dundee and Angus districts of Scotland. METHODS Women diagnosed as having cervical intraepithelial neoplasia and microinvasive or invasive cancer of the cervix in 1989 and 1990 (798 cases). METHODS History of cervical cytology results according to age (age groups of five years) and screening interval (three years and five years). RESULTS Cervical intraepithelial neoplasia was most common in women under 45 (711 cases in women of 45 and under v 38 cases in those of 46 and over). Cervical intraepithelial neoplasia occurring de novo was not seen in women over 50 who had been screened every three years. Microinvasive or invasive cancer of the cervix was diagnosed in 26 women over 50. None of these women had participated adequately in the cervical screening programme. CONCLUSIONS Cervical intraepithelial neoplasia typically occurs in younger women. All women over 50 with an adequate history of negative results on smear testing every three years may be safely discharged from further screening if these findings are confirmed in other populations.