A sympathetic account of Cyrus Vance's three years as secretary of state under President Carter. The author argues that Vance's "unrelenting pursuit of Israeli concessions" was the basis for the successful outcome of Camp David. He faults Vance, however, for failing to anticipate the Soviet invasion of Afghanistan. The account of the domestic forces arrayed against SALT II is especially good. This is volume 20 in the "American Secretaries of State and Their Diplomacy" series.