This book constitutes the refereed proceedings of the 11th International Conference on Product-Focused Software Process Improvement, PROFES 2010, held in Limerick, Ireland, in June 2010. The 28 revised full papers presented together with the abstracts of 2 keynote addresses were carefully reviewed and selected from numerous submissions. The papers are organized in topical sections on software quality assurance; agile software development; software business; software systems; process quality; software measurement; and software process improvement.