This book constitutes the refereed proceedings of the 17th International Working Conference on Requirements Engineering: Foundation for Software Quality, REFSQ 2011, held in Essen, Germany, in March 2011. The 10 revised full papers and the 9 short papers presented were carefully reviewed and selected from 59 submissions. The papers are organized in seven topical sections on security and sustainability; process improvement and requirements in context; elicitation; models; services; embedded and real-time systems; and prioritization and traceability.