The emergence of a European private law is one of the great issues on the legal agenda of our time. Among the most prominent initiatives furthering this process is the work of the Commission on European Contract Law. The essays collected in this 2002 volume have their origin within this context. They explore two practically very important topics which had hitherto been largely neglected in comparative legal literature: set-off and 'extinctive' prescription (or limitation of actions). Professor Zimmermann lays the comparative foundations for a common approach which may provide the basis for a set of European principles. At the same time, the essays provide practical examples of the arguments that can be employed in the process of harmonising European private law on a rational basis. They explore topics such as the comparative experiences in the various modern legal systems and the direction in which the international development is heading.