Action learning has the ability to solve complex problems and to significantly increase the speed and quality of individual, team and organizational learning. Its theoretical base and relationship to adult learning orientations and the source of this power remain relatively unexplored. The authors conducted an extensive review of the literature in order to examine how each of the six critical components of an action learning program (namely; a problem or task, a group, the reflective inquiry process, action, learning, and an action learning coach) incorporates and applies five major adult learning schools (behaviorist, cognitivist, humanist, social and constructivist). An empirical example from the authors' experience is presented to illustrate the extent and range in which action learning incorporates each of the five schools of adult learning. (Contains 1 figure.)