The paper defines action research and what conception of theory might best contribute to its development. Action research is a continuous conscious attempt to seek increased meaning and direction in a teacher's relationship with students. Practical inquiry of teachers with their students is a form of educational research. A Masters Degree Program in Instructional Leadership in which students pursue an internship instead of a formal thesis is described. The internship involves students in proposing and implementing a change in their own teaching situation. A review of curriculum research examines Dewey's practical inquiry approach and the more formalized experimental studies promoted by Thorndike, Cattell, and others. Action research theory is summarized in several points, among them that action research is a spirit of inquiry that strives for meaning and direction in the educative action of teachers, learners, and those who help them. (DWH)