Funds from this grant support efforts by Manabu Shiraiwa, assistant professor of chemistry at the University of California, Irvine, in collaboration with Nicola Carslaw at the University of York, to develop and lead an indoor chemistry modeling consortium. This two-year project will bring together experts from several different fields to begin to develop a model that realistically represents how buildings influence indoor chemical processes. The team will begin to find ways to link six different modeling techniques that deal with different aspects of indoor chemistry on scales ranging from micro- to macroscale and from very short (less than 1 second) to much longer lifetimes. The modeling consortium plans to address the following research questions: (1) Can we understand indoor chemistry well enough to predict it quantitatively with computer models of chemical and physical processes? (2) What are the major uncertainties that currently exist in these models? (3) What experiments/field measurements do we need to improve our models? (4) What experiments/field measurements do we need to evaluate our models? Models will be developed within the framework of exploring two relevant and highly topical research themes for indoor air chemistry: (1) reactions between indoor oxidants and human skin and (2) cleaning-related emissions of volatile organic compounds (VOCs). The research team will also conduct three workshops—at the beginning, middle, and end of the project—to foster collaboration and communication as well as to provide in-person opportunities to review work plans and progress. Six early-career researchers will be trained. The new knowledge and modeling tools will be shared in peer-reviewed publications as well as through presentations at conferences, such as Indoor Air 2018 and the American Association for Aerosol Research (AAAR) meeting.