An overview was presented of the Drake Health Registry Study (DHRS), which was initiated in 1986 because of probable past exposures of Drake Chemical Company workers to the potent bladder carcinogen, beta-naphthylamine (91598) (BNA). The DHRS had five primary objectives: identify former workers and determine vital status; notify, enroll and maintain compliance among as many living cohort workers as possible; establish and maintain a bladder cancer medical surveillance program; evaluate notification and surveillance programs; evaluate bladder cancer risk and total and cause specific cohort mortality risks. Medical screening included standard urinalysis, Papanicolaou urine cytology and quantitative fluorescence image analysis. Free diagnostic evaluation was available following a positive screening test. After 40 months, the cohort comprised 408 persons (6% female), 42 of them presumed deceased. A total of 334 were notified and 81% were current participants. Distribution of registrants by risk group was 72.1% low, 7.3% medium and 20.6% high. Of 254 persons completing at least initial screening, 27 were eligible for and 18 underwent diagnostic evaluation. No invasive bladder tumors were found, but two cases of moderate to severe dysplasia were diagnosed after third screenings. Six male cohort workers were identified as having bladder cancer. Three were identified by cause of death. Latencies between dates of hire and diagnosis were 9 to 26 (average 19) years. For 35 cohort deaths analyzed, standardized mortality ratios were significantly increased for all causes, all cancers, bladder and other urinary cancer (20 to 30 fold excess) and liver cirrhosis. The authors conclude that six to ten new bladder cancer cases among the cohort are likely over the next 20 years.