T HIS study presents some of the basic or common processes which underlie manifestations of formalization in the small group, i.e., the process in which groups create rules and procedures for the dispatch of the business and for the regulation of the members to one another. Formalization is defined here as the process by which groups follow prescribed patterns of procedure; an increasing complexity in the social structure, a progressive prescription and standardization of social relationships and finally, an increasing bureaucratization of the organization. Much of the literature on this subject has pointed out that in the small groupings communication flows naturally, spontaneously and uninterrupted, and as a result contacts between members of the group are of an intimate nature. However, present-day observers are alarmed by the extent these channels of communication between followers and leaders in the small as well as the large formal organizations are lengthened, multiplied, and ossified. It is observed that as an organization develops, the tasks of the leadership or executive board and the office staff not only become more complex, but their duties become elaborate, enlarged, and specialized. The principle of division of labor comes more and more into operation, executive authority and responsibility undergo division and subdivision. There is thus constituted a rigorously defined hierarchical structure of positions. The leading hypothesis may be then expressed in these terms: the extension of the organization's structure starts its common process from an amorphous, informal structure and develops to a formal or regimented one. There is a progression from loose interpersonal to rigid impersonal contacts which is characterized primarily by an organizational hierarchy and by an extensive specialization of function. A voluntary association may be defined as a group of people which has some sort of formal organizational structure in which membership is open to all who share a particular occupation or profess a common aspiration or interest and in which people become members by their own decision. The association functions as a means for the pursuit of social ends. Ten associations were intensively studied by the case history method. These ten associations were: The Minneapolis League of Women Voters; the Ancient Order of United Workmen of Minnesota; Minnesota Council of Churches; Minnesota Nurses' Association; Alano Society of Minneapolis; Minnesota Association of Cooperatives; Lutheran Welfare Society; Minnesota Division, American Cancer Society; Hennepin County League of Planned Parenthood; and The International Institute. These ten associations were selected under the following conditions: (1) The officers of the association had to give approval to the research worker to have full access to all the records of the association; and (2) The association had to have, for the purpose of this study, a fairly rich amount of documentary material. The organizational histories of these associations were constructed from the documentary material taken from the files of the organization, i.e., minutes of board and committee meetings, pamphlets, publications, constitution and by-laws, annual reports, letters, and verbatim interviews with active key personnel past and present. In gathering the data for these case histories an attempt was made to record as completely as possible all the successive changes in the manifest social structure of the association, such as formal membership criteria, specific functional positions of officers, the changes in board and committee structure, the changes in the administrative office procedure, the increases in physical property, elaboration of personnel policies, size of the paid regular staff work-