The “cohabiting couple family” is the fastest growing family type in England and Wales.1 Even if Parliament provides for opposite-sex civil partnerships in the aftermath of the Supreme Court’s decision in R. (on the application of Steinfeld) v Secretary of State for the International Development,2 many people will surely continue to live informally as cohabitants and experience the peculiar legal consequences flowing from that decision. This, along with its inherent quality, makes Barlow’s Cohabitants and the Law immensely useful.3 The last edition of the work was published as far back as 2001, meaning that the new author, the solicitor David Josiah-Lake, faced a mammoth task. Professor Barlow remains an Advisory Editor of the book, which has the objective of “putting together in one place, as much as it is possible to do so, discussion of the laws affecting unmarried/cohabiting families”.4 While it is aimed at those teaching and practising family law, potentially suggesting that it is of only limited interest to readers of this journal, there is in fact plenty here for the property lawyer, particularly in respect of areas falling on the edge of or just outside property law as traditionally understood and taught.