This article reviews issues in screening and surveillance of liver disease in hazardous waste workers. Traditional liver injury tests (LIT) are only insensitive indicators of liver disease. Newer techniques, including the use of true liver function tests and urinary excretion of metabolites, are as yet unvalidated and substantially more expensive. In the presence of abnormalities, useful strategies include: assessment of other possible causes, avoidance of other possible risk factors, and review of exposures on specific sites.