Two thousand one hundred ninety-four patients with abnormal Papanicolaou smears were evaluated by colposcopy without endocervical curettage in the initial part of the series but with routine endocervical curettage in the latter part. Forty-two cases of microinvasion-invasion were all accurately diagnosed with no postcryotherapy occurrence of these lesions. Evaluation of the Papanicolaou smear, colposcopic biopsy specimens, squamocolumnar junction location, and use of surgical removal for severe dysplasia-carcinoma in situ appeared to be most important in the successful outcome. Endocervical curettage played a minor role. Multiple positive cross correlations between Papanicolaou smear severity, colposcopic biopsy specimen severity, squamocolumnar junction nonvisualization, positive results of endocervical curettage, increased lesion size, increased age, and microinvasion-invasion occurrence were all demonstrated.