Public health scientists have produced valuable research about the epidemiology of occupational hazards, their measurement, and engineering controls. Still, many firms do not apply available knowledge to eliminate workplace hazards. Occupational safety and health policy research helps to bridge the gap between current scientific understanding and effective public policies. It focuses on four areas: (1) primary prevention policies, including standards focusing on controlling specific hazards, standards requiring health and safety programs, surveillance, education and training, targeting of enforcement, and nonregulatory safety incentives; (2) secondary prevention policies, including medical care, vocational rehabilitation, and laws and regulations fostering reemployment of injured workers; (3) compensation policies, including the range and level of medical benefits and income benefits to injured workers; and (4) behavioral responses to policies that lead to unintended consequences. This article provides examples of existing research in these areas and discusses the direction of future occupational safety and health policy evaluation research.