From 1979 to 1986, 500 women were enrolled in a New York State regional diethylstilbestrol (DES) clinic for the early detection of DES-associated adenocarcinoma of the cervix or vagina. Only 66 DES-exposed females were seen at Roswell Park Memorial Institute in the 6-year period prior to the establishment of the DES screening clinic. Most (40%) learned of the DES screening clinic through television public service announcements. Documentation by physician, pharmacy, or hospital records of intrauterine DES exposure was possible in only 15.2% of the cases. Because of a mean age of 24 years of the DES-exposed patients, most physician, pharmacy, and hospital records were not readily available from that time period. In 5.2% of the patients enrolled in the DES clinic, review documented that the mother had not taken DES or other synthetic estrogen analogs. Among the 474 evaluable DES patients, gross vaginal or cervical abnormalities were present in 13.5% and DES-associated adenosis was seen in 16.0%. Sixteen (3.4%) developed squamous dysplasia, one developed squamous in situ carcinoma of the cervix, and one developed invasive squamous cell carcinoma of the cervix. During the 6-year period of the DES screening clinic, no patient developed DES-associated adenocarcinoma of the cervix or vagina. The utility of such specialized clinics is discussed.