This brief essay serves as an introduction to a volume of studies by Latin American scholars of constitutional law and theory responding to themes in my work. It outlines the jurisprudential and historical-political background against which my work developed, stressing the important roles played by American Legal Realism and the politics of the 1960s in shaping my thinking. The essay explains how my interest in populist constitutional law and dialogic forms of constitutional review emerged from the same background, but was strengthened by an interest in comparative constitutional law that I developed in the 1990s.