FOR many years the Parker Institute of Columbia University has been engaged in publishing a series of bilateral studies on private international law which by now has come to include 16 titles. But so far there has been no study concerning Mexico, the United States' principal civil-law neighbour. All the more warmly must we welcome the fact that it was two outstanding specialist* from both sides of the border who have now undertaken this task: Siqueiros, an experienced Mexican practitioner, civil servant, law teacher, and scholar and Bayitch, an authority in both continental and American law who has published an outstanding study on the relations between treaties and conflicts law. Since the book is written primarily for readers in the United States and the Commonwealth, the emphasis in Part One (Sources) is on Mexican law which is not easily accessible elsewhere. Part Two, on the civil-law pattern, discusses the status of aliens, Part: Four, Criminal Law, and Part Five, Jurisdictional Conflicts (including proof of foreign law, judicial assistance and arbitration. It is in Part Two where we find the problem of choice of law, happily without the usual space-wasting conceptual speculations. Instead', we have what appears as a complete coverage of the case law of both countries. In reviews of other bilateral studies, I have been compelled to report that, notwithstanding much learned analysis, courts in international conflicts cases, rightly or wrongly have in effect quite regularly applied their own laws, with some very specific exceptions, such as problems of status and the validity of such transactions as contracts, wills, trusts, marriage, adoption, and legitimation. 1 It can hardly be a coincidence that the present book confirms this conclusion. In Mexican relations this seems strangely disturbing in traffic accident cases where Texan prejudice was unhappily sanctioned years ago by no less a judge than Mr. Justice Holmes in Slater v. Mexican National Railways. 194 U.S. 120(1904). In another cruciaf area, the American recognition of Mexican divorces, the law in the United States, as described in the present book (pp. 241-257) is about to undergo a dramatic change due to the change in the divorce laws of New York and California in 1966 and 1969. This book has filled a long felt gap; a rare occurrence, indeed. ALBERT A. EHRENZWEIO.