All philosophers engage in the history of philosophy, and in doing so, they must ask themselves the following urgent questions: How do philosophy and the history of philosophy relate? How should philosophers generally approach the history of philosophy? What fail, and what succeed, as reasons that philosophers who are not historians of philosophy should study the history of philosophy? Philosophy of the History of Philosophy answers these questions in a current, broad, and systematic analysis. Surveying scholarship from the past half century, focusing exhaustively on our three questions, and in reinforcing the answer, Philosophy of the History of Philosophy shows how philosophers should approach the history of philosophy and why non-historically focused philosophers should study it.