Ken also identified the corporation, not "the market,” as the defining institution of modern economic activity, developing these and related themes both in his teaching and in such widely celebrated books as American Capitalism (1952) and The New Industrial State (1967). But his interest in these ideas persisted throughout his life. The central importance of the corporation, and the fear that government was no longer able to provide an adequate countervailing force against corporate influence exerted both legally and otherwise, was the subject of his last book, The Economics of Innocent Fraud.