After an enthusiastic response to the five past International Symposiums held in 1984, 1989, 1994, 1999 and 2005, we are pleased to announce that the 6th International Symposium on Multiphase Flow, Heat Mass Transfer and Energy Conversion will be held in July 11-15, 2009. The focus of the symposium is the fundamental aspects as well as the practical applications at multiphase flow, heat mass transfer and energy conversion in energy, power, chemical, nuclear and petroleum engineering and industry. 　　The conference is intended to provide a platform for active researchers and engineers to exchange information and identify research needs and future development in this important field.