For the scholar who wishes to understand the think tank and its place in American politics, the fundamental problem is that the central concept is fuzzy, mutable, and contentious. As Simon James aptly noted in 1998, "Discussion of think tanks...has a tendency to get bogged down in the vexed question of defining what we mean by 'think tank' – an exercise which often degenerates into futile semantics." In the decade since James wrote those words, the scholarly discussion surrounding think tanks has grown in scope and sophistication. Yet I will argue that the so-called "dilemma of definition" has never truly been resolved. The purpose of this brief paper is to outline an approach to the study of think tanks that overcomes the most pressing difficulties associated with the concept.