Whereas the European and South African law of contracts is today seen as normatively integrated part of the law of obligations that can be explained coherently on the basis of an overarching theory or a set of intellectually related principles, the rest of the law of obligations is apparently still understood as resulting from various causes that are normatively independent and difficult to explain. Accordingly, non-contractual obligations offer a highly disordered picture also from a comparative perspective. The project aims to offer a principled comparative overview over this part of private law. The book will not be about “classification” of obligations, though, but tries to unveil, from a comparative, historical, and analytic perspective, common ideas, principles and rules that structure the legal relations between private individuals in the absence of a contractual agreement.