The purpose of this paper is to prepare a systematic method for explaining religious movements. A systematic study is required to account for the conditions of this special kind of social process and comparison is necessary for this type of explanatory, generalizing research. Consequently, an examination of some concepts and procedures for this research is indispensable. A number of invaluable suggestions and ideas are drawn through a critical consideration of Lucy Mair's comparative study of religious movements. This inspired me to do the present study. The use of the term "religious movement" may be more appropriate in order to grasp the dynamic relatioship between social change and change in religious system. It is necessary, however, both to clarify implications attached to this word and to prescribe a minimum definition of the term "religious movement." Hypothetically, the concept may connote a social attempt by a group of people directed by leaders to overcome the ultimate limits of human ability through the operation of sacred symbols and the development of ideologies. Then, we must distinguish between the earlier stage of starting and the later development processes when discussing religious movements from an analytic point of view. The term "religious movement" means a series of religious phenomena which persist in changing social situations. Thus, to explain the starting stage is one thing and to explain the development process is another. Furthermore when we search for explanative variables, we have to differentiate the inherent elements of the religious movement (or elements in Religious-Culture system) from the extrinsics. Conditions for the start and development process of religious movement consist of these two types of elements. Pointing out the way of reciprocal relation-ship is the object in comparative analysis of religious movements.