Many communities throughout the US are routinely exposed to elevated concentrations of particulate matter (PM) in wildland fire smoke. A common public health message is for people to go indoors when outdoor PM levels are elevated. While PM infiltration in single family homes has been relatively well studied, less is known about how much comes indoors in commercial and nonresidential buildings (such as libraries, fitness centers, and schools). To fill knowledge gaps on smoke infiltration and mitigation indoors, EPA researchers worked with community partners in Montana and California on a multifaceted study called the Wildfire Advancing Science Partnerships for Indoor Reductions of Smoke Exposures (ASPIRE) Study. This study began in 2019 and examined wildfire smoke indoor air quality impacts in public spaces and innovative approaches to reduce wildfire smoke indoors. This presentation will provide an overview of study components and some of the key results.