Indoor nonindustrial work environments were designated a priority research area through the nationwide stakeholder process that created the National Occupational Research Agenda. A multidisciplinary research team used member consensus and quantitative estimates, with extensive external review, to develop a specific research agenda. The team outlined the following priority research topics: building-influenced communicable respiratory infections, building-related asthma/allergic diseases, and nonspecific building-related symptoms; indoor environmental science; and methods for increasing implementation of healthful building practices. Available data suggest that improving building environments may result in health benefits for more than 15 million of the 89 million US indoor workers, with estimated economic benefits of $5 to $75 billion annually. Research on these topics, requiring new collaborations and resources, offers enormous potential health and economic returns.