This volume contains the papers accepted for presentation at the 15th Wo- ing Conference on Requirements Engineering: Foundation for Software Quality (REFSQ 2009), held in Amsterdam during June 8-9, 2009. Since 1994, when the ?rstREFSQ tookplace, requirementsengineering (RE) has never ceasedto be a dominantfactor in?uencing the quality of software, s- tems and services. Initially started as a workshop, the REFSQ working conf- ence series has now established itself as one of the leading international forums for discussing RE in its many relations to quality. It seeks reports on novel ideas and techniques that enhance the quality of RE products and processes, as well as re?ections on current research and industrial RE practices. One of the most appreciated characteristics of REFSQ is that of being a highly interactive and structured event. Each session is organized in order to provokediscussion among the presenters of papers, discussants and all the other participants.Typically, after a paper is presented, it is immediately discussed by one or two pre-assigned discussants, then subject to a free discussion involving all participants. At the end of each session, an open discussion of all the papers presented in the session takes place. REFSQ 2009 maintained this tradit

This book constitutes the refereed proceedings of the 13th International Working Conference on Requirements Engineering: Foundation for Software Quality, REFSQ 2007, held in Trondheim, Norway in June 2007.

The 27 revised full papers presented together with 1 keynote lecture were carefully reviewed and selected from numerous submissions for inclusion in the book. The papers are organized in thematic sections on goal-driven requirements engineering (RE), products and product-lines, value-based RE and the value of RE, requirements elicitation, requirements specification, industrial experience of RE, and requirements quality and quality requirements. Within these themes, the work presented spanned a range of application domains from business systems to air traffic management, used techniques that varied from ethno-methodology to formal specification and delivered requirements for both custom systems and software product lines.