Presenting a new approach to the problem of public authority liability, this volume provides a theoretical foundation in the form of principles of administrative liability that are both normatively sound and consonant with other recognized legal principles. These principles are used as criteria by which to judge the current law and as a guide to reform. Such reform could be brought about by judicial development of the law, and this volume explains how. It considers both the procedural and the substantive divides between public and private law and explains the proposed solution's relation to the forms of public authority liability already present under European Community law and the Human Rights Act. Focusing in particular on UK law, the book is also relevant to other Commonwealth countries and will be of interest to scholars and practitioners of both tort and public law.