American society is undergoing rapid transformation, driven in part by changes in communications technology, demographic shifts, and political realignments. The American Demographics Project (ADP) will describe these national changes affect the character and contours of American life, to chronicle the speed and size of opinion shifts in the US. This project will rely on a substantial national survey of at least 20,000 adults, enabling a detailed analysis of patterns of behavior, religious beliefs, and political attitudes. The ADP will describe religious, racial and ethnic, and political identities of Americans, track changing social relationships and experiences in far greater detail than permitted in the average poll, and far more regularly than government surveys. For instance, we will be able to track the changing politics of Mormons, document emerging cultural realignment among young white evangelical Protestants, the diversity of the country’s growing unchurched communities, rising religious and racial diversity among married couples, and the evolving approach to religious and spiritual life that are redefining American community life in urban centers and small towns.