This chapter examines the electoral coalitions of both the Republican and Democratic parties. A heavy emphasis will be placed on mapping partisan change from the 1960s to the present, explaining how and why change took place, and examining the meaning and implications of change. It focuses on where the parties are now in terms of their coalitions, and some speculation on where they might be headed in the future. The electoral coalitions of both the Republican and Democratic Parties have changed a good deal over time. Part of this coalitional evolution is due to the social change that has been a constant feature of American society. The Democratic and Republican parties are constantly taking the measure of American society, trying to determine how—given the broad, programmatic goals of the party—they can best appeal to voters and gain control of government through victory on election day.