The theory of the exoteric-esoteric system (kenmitsu taisei), proposed by Kuroda Toshio more than twenty year ago, has exerted a profound influence on the study of Japanese history and religion. The time has come for a thorough reexamination of both the contributions and deficiencies of Kuroda's theories. This essay outlines the development of Kuroda’s thought, examines the contributions of the kenmitsu taisei theory, and discusses a number of remaining issues.