Analytical jurisprudence became popular almost instantly in 1961 with the publication of H.L.A. Hart’s The Concept of Law, but as readers familiar with this classic text know all too well, Hart included no sustained discussion of the particular method he employed to arrive at some of the most distinctive claims discussed in contemporary legal theory today. Many have supposed that Hart was simply engaged in conceptual analysis, a common philosophical technique of discerning necessary and sufficient conditions of some concept by a priori reflection on possible instances to see where our linguistic intuitions lie. On the basis of this method, we learn about the concept of law by making explicit what is already implicit in our knowledge of law. No new experience or neutrality-compromising interests are invited or required. It might have been possible for legal philosophers working during Hart’s time to follow him in assuming rather than explaining the use and goals of analytical jurisprudence, but this is no longer possible for the current generation. The association of analytical jurisprudence with conceptual analysis of law, and the persistent attack on conceptual analysis both within and outside legal philosophy, have forced analytical legal theorists to make plain the nature of their method, and investigate any connections it might (or might not) have with familiar forms of conceptual analysis. This book offers some initial steps towards this objective. I aim to demonstrate that the challenges often levelled against analytical jurisprudence, and especially its perceived use of conceptual analysis, help to show – perhaps surprisingly – that conceptual theories of law such as Hart’s are not in fact best understood as the results of conceptual analysis, but instead of constructive conceptual explanation of law. While conceptual analysis concerns itself with elucidating or making explicit what is already implicit in some particular culture’s self-understanding of law, constructive conceptual explanation attempts to correct, revise or improve on what might be mistaken, distorting or parochial in that self-understanding when tested against observable social reality.