Discrepancies among classification systems of Papanicolaou smears and lack of communication between cytologist and clinician are not uncommon. An attempt should be made by the cytologist to estimate, on a percentage scale, the likelihood of any given smear indicating carcinoma. This enables a more realistic and systematic management of a patient whose smear is other than negative. Proper technique in obtaining the smear is essential to proper interpretation, and it must be stressed that a negative smear in a patient with a cervical lesion does not rule out carcinoma. Likewise, a negative smear cannot rule out carcinoma higher in the generative tract.