This book constitutes the refereed proceedings of the International Symposium of Formal Methods Europe, FME 2001, held in Berlin, Germany, in March 2001. The 32 revised full papers presented together with abstracts of three invited talks were carefully reviewed and selected from a total of 72 submissions. Focusing on increasing software productivity, all current aspects in formal methods are covered. Among the application areas addressed are avionics, smart cards, financial engineering, E-commerce, middleware, security, telecommunications, etc.