Chronic beryllium (7440417) disease or berylliosis was reviewed with regard to occurrence, clinical signs, diagnostic strategies, and preventive measures. Lung biopsy of most cases of berylliosis occurring since 1960 showed the presence of characteristic sarcoid like epithelioid granulomas similar to those seen in cases of idiopathic sarcoidosis. Berylliosis patients and sarcoidosis patients both showed liver, skin, lymphatic, and lung involvement; suppressed T-lymphocyte function; and similar infiltrates in lung tissue. Differences between the two types of patients were discussed with respect to age, radiographic changes, and extrapulmonary manifestations of disease. Epidemiological studies showed that berylliosis was an idiosyncratic disorder requiring a host factor in addition to beryllium exposure and that disease occurrence was related to both the form and dose of beryllium exposure. Industries and trades with potential beryllium exposure included ceramics and electrical connectors, nonferrous foundries and smelters, sandblasting, aerospace, electronics, refractories, beryllium smelting and fabrication, tool and die making, soldering and welding, and hazardous waste processing (SIC-4953). The manufacture of nuclear control equipment, dental equipment and supplies (SIC-3843), engineering and scientific equipment, mechanical measuring equipment, automotive parts, and telecommunication equipment also presented some risk for berylliosis. The authors note that new exposure settings are being monitored for future control of berylliosis and secondary prevention, including the definition and validation of a sensitive diagnostic test.