The assumption that all labor organizations may be traced back to some one original form of local trade society is unwarranted. Labor organizations of different types and located in different communities are the products of environmental conditions and forces which have caused the wage-earners to cohere in some weak or strong form of union organization. Because of increasing population, the elimination of free land, rising prices, or other social phenomena, American wage- earners have been vividly impressed with the insufficiency of individual bargaining. Organization is naturally the next step. Wage-earners organize in order that wages may be raised, hours reduced, or conditions of work improved. The form of the organization is not the significant fact; nor is the expressed function of the union whether business, revolutionary or " predatory " of great importance But classification may help students of labor problems in their effort to investigate the complex of union origins, structures, methods and functions.