The use of biologic monitoring, medical screening, and surveillance techniques in the workplace were reviewed with regard to worker exposure and prevention of occupationally related diseases. A continuum of prevention incorporating primary, secondary, and tertiary levels was presented as a theoretical construct. The primary level included elimination of exposure, engineering controls, personal protection, and biological and environmental monitoring. The secondary level focused on medical screening to detect any disease process for treatment and prevention. The tertiary level was associated with the appropriate treatment of the disease once detected. The National Occupational Hazard Survey (NOHS) of 1972 to 1974 provided an initial profile of biological and medical screening and indicated that factors other than specific job related hazards determined the prevalence and occurrence of screening. Precepts for a screening program in the industrial environment were proposed based on precepts in place for community screening. Gaps in national surveillance data systems were identified based on a 1980 study by the National Center for Health Statistics involving a review of 64 environmental health data systems. Problem areas contributing to underreporting included former occupational information, vital statistics, work related diseases with long latencies, state to state variations, computer coding, passive disease register systems, lack of standardization, and low dose level reporting. The authors conclude that public health data collection must utilize surveillance and screening at the plant, state, and national level in order to better design and improve existing health policies and implementation programs.