This book constitutes the post-proceedings of the Third International Computer Music Modeling and Retrieval Symposium, CMMR 2005. The 24 revised full papers address a broad variety of topics, organized in topical sections on sound synthesis; music perception and cognition; interactive music: interface, interaction, gestures and sensors, music composition; music retrieval; music performance, music analysis, music representation; as well as interdisciplinarity and computer music.