The present volume presents a part of the results of a research project launched by the European Science Foundation (ESF) in 1977. Tribute should be paid to the late Professor Aleck Chloros, Judge in the Court of the European Community, whose belief in the European ideal and enthusiasm for European cooperation and the comparative study of legal problems made him an elo quent advocate of a large-scale ESF venture into the field of com parative law. Judge Chloros had envisaged the creation of a per manent, sizable and well-equipped European institute for compa rative legal studies. The successive working parties convoked by the Executive Council of the ESF, which I had the honour of chairing from the beginning, came to the conclusion that this am bitious vision could not be realized immediately; the financial sit uation of the member organizations of the ESF also deteriorated, making a cautious approach a necessary virtue. The solution ulti mately adopted by the last of the working parties - the Ad Hoc Committee for Comparative Law -and submitted to the General Assembly of the ESF in 1979 called for the launching of four pi lot projects. In November 1980, the Assembly approved detailed plans for two of these projects. The first of these - dealing with medical responsibility - has already been presented in an impres sive volume (E. Deutsch and H. -L. Schreiber, editors, Medical Responsibility in Western Europe.