Public concern over the so called “trust problem” in the United States between the end of the nineteenth century and 1914, the year of the passage of the Clayton and Federal Trade Commission (FTC) Acts, was reflected in the considerable contemporary literature on the subject. Not surprisingly, professional economists actively participated in this debate. Their thinking directly and indirectly influenced the legislation of 1914 in a way that cannot be said of the Sherman Act of 1890 (Mayhew 1998). A survey of the most important of these professional writings shows that, among the several voices animating the discussion, John Bates Clark's was perhaps the most influential. In this connection, Joseph Dorfman argues that John Bates Clark's second edition of his Control of Trusts (1912), co-authored with his son John Maurice, “played a formative historical role in policy making, for it provided the most systematic exposition of the view on trusts, that was embodied in 1914, at President Woodrow Wilson's urging, in the Clayton Act and the FTC Acts.” “From this standpoint,” continues Dorfman quite emphatically, “The Control of Trusts caught the dominant reform interest and in turn became a contributing force in shaping the trend of the socio-economic development of the nation” (1971, p. 17). Apart from the 1912 monograph, John Bates Clark devoted considerable attention to the problems of trusts and industrial combinations during much of his career, both in his professional writings and in his frequent contributions to newspapers and popular reviews.