The refereed proceedings of the 8th International Conference on Reliable Software Technologies, Ada-Europe 2003, held in Toulouse, France in June 2003. The 29 revised full papers presented together with 3 invited papers were carefully reviewed and selected from numerous submissions. The papers are organized in topical sections on Ravenscar, language issues, static analysis, distributed information systems, software metrics, software components, formal specification, real-time kernel, software testing, and real-time systems design.