This study showed the efficacy of large loop excision of the transformation zone (LLETZ) in the management of cervical intraepithelial neoplasia (CIN). Eighty-three women with abnormal cervical cytology were recruited. Colposcopic examination and directed punch biopsy were performed and the women had LLETZ therapy as an outpatient procedure. There were 2 cases of microinvasive cervical carcinoma that were missed by directed punch biopsy, the diagnosis being made after the patients underwent LLETZ treatment. There was a large disparity in the histological analysis between directed punch biopsy and LLETZ specimen. This disparity would not have been detected if the women were treated by ablative methods. In women with cervical dysplasia, LLETZ procedure is preferred as the whole excised lesion can be examined histologically and diagnostic error is reduced.