This contribution reviews several catalytic reactions in multiphase systems including dense phase CO2 and other counter liquid or solid phases such as organic liquids, poly(ethylene glycol), water, ionic liquids, fluorous liquids, solid acid/bases powders, and supported metal particles. The features and potentials of dense phase CO2 for the multiphase catalytic reaction and separation will be presented. (C) 2008 Elsevier B.V. All rights reserved.