Endocervical samples were obtained from 435 females for Chlamydia detection by using both a Dacron swab and a cytobrush. Positive results were obtained from 35 swabs and 34 cytobrush specimens. All specimens positive with the cytobrush were detected also with swab samples. The cytobrush and Dacron swab appear to be comparable for the detection of endocervical infections with Chlamydia trachomatis.