Despite its inclusion in models of social and ecological determinants of health, work has not been explored in most health inequity research in the United States. Leaving work out of public health inequities research creates a blind spot in our understanding of how inequities are created and impedes our progress toward health equity. We first describe why work is vital to our understanding of observed societal-level health inequities. Next, we outline challenges to incorporating work in the study of health inequities, including (1) the complexity of work as a concept; (2) work's overlap with socioeconomic position, race, ethnicity, and gender; (3) the development of a parallel line of inquiry into occupational health inequities; and (4) the dearth of precise data with which to explore the relationships between work and health status. Finally, we summarize opportunities for advancing health equity and monitoring progress that could be achieved if researchers and practitioners more robustly include work in their efforts to understand and address health inequities. (Am J Public Health. Published online ahead of print January 18, 2018: e1-e6. doi:10.2105/AJPH.2017.304214).