Positive Obligations in Criminal Law is a collection of essays rather than a monograph,_x000D_ loosely unified by a concern with the positive duties owed by citizens and/or the state, as the title might suggest. Certainly, there are essays that engage directly with positive obligations, including those on omissions (Chapter 2), human rights (Chapter 8) and, perhaps less obviously, ignorance of the law (Chapter 3). Other essays, such as those on strict and constructive liability (Chapters 4, 5) and on riskbased possession offences (Chapter 6), are really only tangentially connected to that theme. Yet the book is none the worse for that. In truth, it is a collection of somewhat disparate but individually excellent essays on some central topics in the criminal law. As such, the collection is likely to be an important point of reference for many years to come.