This essay reviews Excusing Crime, by Jeremy Horder, Reader in Criminal Law and Tutor in Law at Worcester College, Oxford. It describes Horder’s project, which is to build a complex taxonomy of criminal law excuse practices and to use that account of “why things are as they are” to argue, on the basis of his version of liberal theory, against “the restricted range” of excuses in the UK and elsewhere. By virtue of his appreciation that some, but not all, excuses contain justificatory elements, and given his insistence that pure claims of non-responsibility are not excuses, Horder has defined a field of study that is both broader and narrower than many of his readers are likely to expect. This reconfiguration permits Horder to explore the “theoretical underpinnings” of existing excuses along three intersecting “dimensions.” The effort provides the reader with new analytic tools to organize and understand the seemingly unruly universe of excusing practices in English and American criminal law, and it is the principle contribution of the book. This careful use of description and analysis to construct an “anatomy” of existing excuses in order to support claims for new excuses is the best kind of criminal law scholarship.