This book constitutes the thoroughly refereed proceedings of the 9th International Conference on Entertainment Computing, ICEC 2010, held in Seoul, Korea, in August 2010, under the auspices of IFIP. The 19 revised long papers, 27 short papers and 33 poster papers and demos presented were carefully reviewed and selected from numerous submissions for inclusion in the book. The papers cover all main domains of entertainment computing, from interactive music to games, taking a wide range of scientific domains from aesthetic to computer science.