This volume consists of papers which, in earlier versions, were presented at two seminars held by the Society of Public Teachers of Law. Five chapters are concerned with aspects of tracing and money laundering, another five are concerned with most of the defences applicable to restitutionary claims. The final, and most important, chapter is to some extent an overview of the foregoing chapters and a summary of the discussion at the seminars, but it is mainly an opportunity for the editor to set out his own views.

The first hurdle any reader of the section on tracing must overcome is a terminological one. “Tracing” is used in a variety of ways. For some contributors (Matthews, Moriarty, Norman, Gleeson) tracing is the ability to make a claim to an asset which has undergone some physical change (e.g., a mixture) or is the substitute for the claimant’s original property. For others (Birks, Hayton) “tracing” rules are rules of identification. For Professor Birks tracing is merely the technique by which “value in one asset at one point of time is located in another asset at some time later” (cf. Millett, L.J., in Boscawen v. Bajwa [1996] 1 W.L.R. 328, 334) and should be distinguished from the process of following value from one person to another. The ability to trace may be a necessary incident to a claim, which is usually restitutionary, but is not the claim or remedy itself.

While it is true that the artificial rules for identifying value (e.g., “first in, first out”, “everything is presumed against a wrongdoer” and the pari passu rule) are employed in contexts other than the making of a proprietary claim (e.g., Clayton’s Case (1815) 1 Mer. 572) and we ought to have different labels for different things, I am sure that most lawyers use “tracing” to mean a proprietary claim to an asset. Indeed, it is far from clear that the rules for identifying value are the same regardless of the claim being made (e.g., are the rules for identifying value different at common law and equity, however unjustifiably?) or that they should be (e.g., should “everything be presumed against a wrongdoer” where a proprietary claim is sought, as that presumption works against the wrongdoer’s creditors?).

Despite these and other terminological difficulties, this half of the book is a fascinating exploration of the theoretical and legal limits of tracing. There is inevitably a considerable overlap in the issues and case law discussed. The balance is, perhaps, too heavily in favour of the analysis