This book constitutes the refereed proceedings of the 8th International IFIP WG 2.13 Conference on Open Source Systems, OSS 2012, held in Hammamet, Tunisia, in September 2012. The 15 revised full papers presented together with 17 lightning talks, 2 tool demonstration papers, 6 short industry papers, 5 posters and 2 workshop papers were carefully reviewed and selected from 63 submissions. The papers are organized in topical sections on collaboration and forks in OSS projects, community issues, open education and peer-production models, integration and architecture, business ecosystems, adoption and evolution of OSS, OSS quality, OSS in different domains, product development, and industrial experiences.