The fields of occupational safety and health (OSH) and public health have become disconnected, but recent developments point to ways to reverse this widening gap. Within public health, the need to address health disparities in the US population has brought about a renewed emphasis on social and environmental determinants of disease. OSH offers a way to reach a large portion of the population experiencing these disparities. But to reconnect public health and OSH and truly improve the health of working populations, both disciplines need to recommit themselves to the health of workers. In recent decades, there has been a shift in public health away from environmental determinants of disease to a focus on individual risk-taking behaviors. Workplace public health practice has focused on personal behaviors related to smoking, diet, drinking, and exercise, while deemphasizing physical exposures and stressful working conditions. This shift reflects a broader political trend toward reducing corporate social and environmental responsibility. Behavior-based safety programs have become prominent, directing attention toward “accident-prone” workers rather than redesigning hazardous processes. In the extreme, these programs punish workers while ignoring occupational hazards, with serious negative consequences. For example, many unions and working people recognize that smoking is a health threat, but they are mistrustful of worksite health promotion programs that provide smoking cessation services but ignore workplace safety concerns. As government policies favored funding for mechanistic research on disease causation, many OSH scientists shifted away from studying working populations to studying individuals (or molecules). At the same time, industrial hygienists—once considered workplace public health practitioners—have come under increasing pressure to make themselves relevant to management interests. As a result, their main function has become protecting the health of companies, rather than protecting the health of workers. This has led to the sad situation of the American Industrial Hygiene Association’s refusing to support the Occupational Safety and Health Administration’s ergonomics standard. Disregarding workers both harms workers and leads to impoverished public health solutions. Workers have much to contribute to the reduction of both occupational and environmental hazards. Their familiarity with work processes gives them unique perspectives on process redesign. Discounting this knowledge reinforces the tendency to look for “end-of-pipe” pollution controls that forestall contaminant releases, neglect the root causes of hazards, and constrain production rather than stimulate innovation. Four conceptual frameworks hold promise for reconnecting OSH and public health to the overall health of working people. The first is ecosocial theory, which integrates social and biological analyses of disease distribution using a multilevel, dynamic, and historical approach to explain health inequalities. The second is integrated workplace intervention models that address both individual risk-taking behaviors and environmental risk factors. Third is the life-course approach, in which the effects on health status of cumulative life experiences, including occupational exposures, are evaluated. Finally, sustainable production seeks integrated solutions to occupational and environmental hazards through primary prevention, using participatory designs to improve safety rather than relying on end-of-pipe pollution control. The health of workers may be most effectively advanced by expanding the scope of OSH beyond the constraints of the workplace to embrace the whole lives of workers—in their homes and communities and over the life course.