This editorial introduces the theme of the symposium which addresses the most recent advances in the field of the nationalization of electoral politics. After a decade of an increasing number of contribution in this field, the symposium takes stock of the diversity of applications of nationalization studies, the progress in data collection, and its innovative methods in designs including it as both a dependent and independent variable and analyzing it both for legislative and presidential elections. The editorial reviews the growth and diversification of the literature over time and illustrates in what directions it has evolved mapping out an increasingly rich and complex theory. It links the articles of the symposium to this evolution of t...