The recent financial crisis has questioned whether existing contracts may be adapted, terminated or renegotiated as a result of unexpected circumstances. The question is not a new one. In medieval times the notion of clausula rebus sic stantibus was developed to cope with such situations, and Germany introduced the theory of Wegfall der Geschäftsgrundlage. In England, the Coronation cases provided one possible answer. This comparative study explores the possibility of classifying jurisdictions as 'open' or 'closed' in this regard.

List of contributors; General editors' preface; Preface; List of abbreviations; Part I. Introduction and Context: 1. Introduction: an approach to the issues and doctrines relating to unexpected circumstances Ewoud Honduis and Hans Christoph Grigoleit; 2. Legal history Andreas Thier; 3. Law and economics: the comparative law and economics of frustration in contracts Marta Cenini, Barbara Luppi and Francesco Parisi; Part II. Overview: 4. Overview: concepts dealing with unexpected circumstances; Part III. The Case Studies Ewoud Honduis and Hans Christoph Grigoleit: 5. Questionnaire; 6. The case studies; Part IV. General Comparative Remarks: 7. General comparative remarks: converging tendencies, remaining differences and the unsolved mystery of adjustment Ewoud Honduis and Hans Christoph Grigoleit; Appendix. Some texts on change of circumstances; Selected bibliography; Index.