Dear colleagues: The 9th International Conference on Positron and Positronium Chemistry, PPC-9, will be held at Wuhan University, Wuhan, China, from May 11-15, 2008. PPC-9 will cover progress in fundamental aspects of positron and positronium chemistry, applications of positron annihilation spectroscopy to polymer and other materials, and the advances in experimental techniques. The workshop will include plenary and invited talks, contributed presentations (oral and poster sessions).In line with the tradition of PPC, no parallel sessions will be held. The conference Proceedings will be published in Radiation Physics & Chemistry. The working language of conference will be English.