These tributes by a president and a speaker of the House more than twenty-eight years apart are high praise for two organizations that are both commonly known as think tanks. Yet, in their praise, Johnson and Gingrich characterize the accomplishments of these organizations in notably different terms: Brookings for its “painstaking research” and “objective writing,” Heritage for its “far-reaching” efforts in the “war of ideas.” These characterizations evoke two quite different images and suggest quite different understandings of the role of think tanks in American politics. The first emphasizes their role as producers of credible expertise; the second highlights their contributions to polemical debates over ideas.