This article analyses the changing role of the principal in Mexico, during a period, 1921-1934, in which the configurations sustaining and surrounding schooling were profoundly transformed. It compares the experience of three "directores" working in towns that differed in their expectations and relationship to state and federal government. In this context, the classic "dual personality" of principals is played out in the tense relationship between answering to communities and executing federal policies. I argue that the making of modern school principals is a process that is strongly intermeshed with the emergence a school system as one of the facets of modern state formation. (Contains 43 footnotes.)