The market for this analysis of the structure of trade unionism is largely limited to those already interested in exploring the machinery behind the front of trade unionism, either because of practical interest as a trade unionist, or because organization is extending into an area in which the inquiring individual is concerned. Students of labor relations, too, will find this of historical value. The author was a member of the National Labor Relations Board and taught at Antioch and at Johns Hopkins. This is a posthumous work. In its pages he has presented his findings on the nature, the organization, the functions of trade unions in America, taking his examples from various types of unions, and discussing the issues raised by unionism as such coming to grips with public policy. An important book in a sharply limited field.