We identified nine new cases of biopsy-confirmed chronic beryllium disease among 505 employees and ex-employees in a company that had manufactured beryllia ceramics from 1958 through 1975. Of tests commonly used in medical surveillance, only a confirmed blood beryllium lymphocyte transformation test had a high positive predictive value for beryllium disease (100%). However, two beryllium disease cases had either a normal or inconsistently abnormal blood test and were identified for diagnostic workup by abnormal chest radiograph. The only risk factor for beryllium disease was beryllium exposure; smoking or allergic history did not affect risk. Degree of beryllium exposure was associated with disease rates, which ranged from 2.9% to 15.8% for beryllia-exposed subgroups. One case of beryllium disease occurred in a "dust-disturber" who did not report past beryllium exposure and who began employment 8 years after commercial beryllia production had stopped. Our data support efforts to prevent beryllium disease by lowering beryllium exposures and to identify subclinical and early disease by broad-based medical surveillance using the blood beryllium lymphocyte test and chest radiograph in beryllium-using industries.