white-collar workers, broad occupational grouping of workers engaged in nonmanual labor; frequently contrasted with blue-collar (manual) employees. American in origin, the term has close analogues in other industrial countries. Managers, salaried professionals, office workers, sales personnel, and proprietors are generally included in the category. Professionals and managers, however, are occasionally excluded. Since World War II the number of white-collar workers in the U.S. labor force has increased dramatically. Today they account for almost 50% of the labor force, outnumbering blue-collar workers by approximately 11 million persons. There is considerable difference of opinion concerning the political and social attitudes of white-collar workers. Some authorities, such as C. Wright Mills, author of White Collar (1951), contend that members of the group identify with the institutions for which they work and hence tend toward political conservatism. Others, pointing to white-collar unions such as the American Federation of Teachers and the Distributive Workers of America, claim that white-collar workers tend to identify with manual laborers and others who do not own the means of production.