Computer Safety Reliability and Security : 20th International Conference SAFECOMP 2001 Budapest Hungary September 26–28 2001 Proceedings This book constitutes the refereed proceedings of the 20th International Conference on Computer Safety Reliability and Security SAFECOMP 2001 held in Budapest Hungary in September 2001.The 20 revised full papers presented together with three invited papers were carefully reviewed and selected. The book offers topical sections on reliability assessment and security safety case and safety analysis medical systems human machine interface COTS components off the shelf testing formal methods and control systems