Intense partisan polarization has characterized American politics for more than a quarter of a century. Polarization has left its mark on public opinion, electoral politics, the internal workings of political institutions and the policies produced by these institutions. Because of its impact on various aspects of American politics, the study of polarization has attracted the attention of numerous academics, journalists, and politicians as well. Fleisher and Bond provide an understanding of the causes and consequences of the partisan polarization that has gripped American politics for the past twenty-five years. This book presents a synthesis of the extensive academic literature on various aspects of partisan polarization in contemporary American politics as well as original data analysis in a way that will be accessible to undergraduate and beginning graduate students.