The wildland-urban interface (WUI) is the area where structures and other human development meet or intermingle with undeveloped wildland, and it is where wildfires have their greatest impacts on people. Hence the WUI is important for wildfire management. This document and associated maps summarize the extent of the WUI in the conterminous United States in 2010. The maps and summary statistics are designed to inform both national policy and local land management concerning the WUI. The data presented here summarize the 2010 WUI at a national scale and for each of the 48 conterminous States. All products of this assessment-including maps, statistics, and the WUI GIS dataset-can be accessed at http://www.nrs.fs.fed.us/data/WUI.