This book constitutes the refereed proceedings of the Third International Conference on Product Focused Software Process Improvement, PROFES 2001, held in Kaiserslautern, Germany, in September 2001. The 27 revised full papers presented were carefully reviewed and selected from numerous submissions. The papers are organized in topical sections on quality of software, software process assessment and improvement, organizational learning and experience factory, industrial experiences and case studies, software and process modeling, and empirical software engineering.