A prospective, randomized study was performed to compare the efficacy of a combined endocervical and ectocervical nylon brush with the cotton-tipped swab and wooden spatula for obtaining cervical cytologic specimens. Strict objective criteria were used to determine the adequacy of Papanicolaou smears on the basis of the number of cells present. The two methods were equally effective in collecting ectocervical smears. However, 96% of endocervical smears obtained with the nylon brush contained greater than 50 cells, compared with 58% of swab and spatula smears. Only 1.4% of brush samples contained no endocervical cells, versus 19% of swab and spatula smears. The presence of endocervical cells confirms adequate sampling of the transitional zone. Use of the cytologic Papanicolaou brush may result in fewer false negative and inadequate Papanicolaou smears.