Presidential scholar John P. Burke systematically and thoroughly reviews the office of national security advisor from its inception during the Eisenhower presidency to its latest iteration in the White House of George W. Bush. He explores the ways in which the original conception of the national security advisor - as an 'honest broker' who, rather than directly advocating for any certain policy direction, was instead charged with overseeing the fairness, completeness, and accuracy of the policymaking process - has evolved over time. In six case studies, he analyzes the implications of certain pivotal changes in the advisor's role, providing thoughtful and sometimes critical reflections on how these changes square with the role of 'honest broker'. Finally, Burke offers some prescriptive consideration of how the definition of the national security advisor's role relates to effective presidential decision making and the crucial issues of American national security. "Honest Broker?" will be an important resource for scholars, students, political leaders, and general readers interested in the U.S. presidency, foreign policy, and national security.