This book constitutes the refereed proceedings of the 7th International Conference on Fundamental Approaches to Software Engineering, FASE 2004, held in Barcelona, Spain, in March/April 2004.

The 22 revised full papers and 4 tool presentation papers presented together with an invited paper and the abstract of another invited talk were carefully reviewed and selected from a total of 98 submissions. The papers are organized in topical sections on objects and aspects, smart cards, components, security and web services, modeling and requirements, testing, and model checking and analysis.