The choice of law rules for “contractual obligations” have undergone fundamental change. They require an interpretation which will make them, and their underlying structure, accessible to the busy practitioner and to the scholar. To this end, three essentials may be identified. On two of them Dr Kaye’s new book, dealing with the new law mainly by way of article-by-article commentary, scores highly. First of all, easy access to the text. It is an enormous benefit to have reproduced the English, French, Italian, Dutch and German texts of the Conventions. Experience with the Brussels Convention on jurisdiction and judgments has shown that recourse to the foreign language texts will sometimes provide the vital insight which is invisible from the one-eyed perspective of the English version. It is therefore doubly helpful to have a commentator as adept as Dr Kaye in drawing attention to the inferences open to be drawn from these linguistic and stylistic variations. Secondly, ideas and lines of argument which allow the reader to see how the new rules may apply to, or be bent around, a particular problem. Here there is no doubt that most of the ideas available are to be found in this book. It is a veritable reservoir of material from which arguments may be constructed. Not only that, but the analysis of other writers is set out, fairly and accurately, and the reader permitted to reach his own conclusion as to what the law actually is. This is a service to the legal community whose value should not be underestimated.