This book constitutes the refereed proceedings of the 9th International SPIN Workshop on Model Checking Software, held in Grenoble, France in April 2002 as a satellite event of ETAPS 2002. The 10 revised full research papers presented together with the abstracts of four invited papers or tutorials, three reports on work in progress, three invited industrial presentations, and four SPIN model checking tool descriptions were carefully reviewed and selected from 20 submissions. The book presents state-of-the-art results on the analysis and verifications of distributed and concurrent systems using the SPIN model checker as one of the most powerful and popular such system.