R. C. Edwards' recent work, The Contested Terrain: The Transformation of the Workplace in the Twentieth Century involves an attempt to integrate works on American labour markets. Edwards' thesis, based upon evidence culled exclusively from the United States, is that the working class is divided into three fractions. Edwards argues that the tripartite structure of the contemporary working class is the direct consequence of the three kinds of labour control system that underpin the three major labour markets that characterize advanced capitalist societies. For Edwards, capitalism is defined by the commodity form of labour or, more precisely, the purchase of labour power. Historically, three different combinations of these elements of 'forms of control' have evolved to deal with the problems of coordination in the capitalist enterprise: 'simple', 'technical' and 'bureaucratic'. Edwards subscribes to a romantic view of the underlying, pristine unity of all elements of labour. This is naive and unjustified even with regard to the manual working class.