Residual disease was identified in the hysterectomy specimen in 19 of 65 patients (29%) previously found to have cervical intraepithelial neoplasia and in four of 19 (21%) found to have early stromal invasion on histologic examination of a cone biopsy. Residual disease was found in six of 34 cases (18%) of cervical intraepithelial neoplasia and zero of 12 cases of early stromal invasion after complete excision, and in 13 of 31 cases (42%) of cervical intraepithelial neoplasia and four of seven cases (57%) of early stromal invasion after incomplete excision by cone biopsy. Sixteen of 28 women (57%) with abnormal cytology after cone biopsy were found to have residual disease at the time of hysterectomy. In contrast, no residual disease was found in 35 patients who had no evidence of cytologic abnormality after the initial treatment. The finding of abnormal cytology after cone biopsy is shown to be a more useful prognostic indicator than histologic examination of excision margins. Therefore, we believe that a policy of expectant management, based on regular cytologic examination, is justified when histologic assessment has shown the lesion to extend to the line of excision.