The overriding theme of this very insightful work from distinguished presidential scholar Fred I. Greenstein is stated in the opening pages: “The United States is said to have a government of laws and institutions rather than individuals, but as these examples remind us, it is one in which the matter of who occupies the nation's highest office can have profound repercussions” (p. 2). Greenstein's analysis of presidential leadership styles from FDR to Clinton corroborates his theme by demonstrating the extent to which the aggrandizement of the presidency since the New Deal has left the American polity at the mercy of the skills and personalities of the holders of the office. As Greenstein himself points out (p. 3) parliamentary systems, with their more collective leadership, place more partisan and institutional constraints on the head of government. In contrast, the centrality of the presidency to the American system of government since the New Deal and the extent to which the institution is driven by the individual style of respective officeholders provide a recurrent and pervasive element of instability in American national government. Yet this very instability is also perhaps the office's most useful attribute. In a system characterized largely by gridlock it provides intermittent and necessary innovation and dynamism. The presidency's' greatest shortcoming, its highly protean nature, is also, ironically, its greatest value as a political institution.