Recent progress of mixed oxide catalysts has been surveyed briefly, and future opportunities of catalytic technology are discussed, taking for example solid heteropolyacid and perovskite catalysts, where some promising signs for the future are noted. It was stressed that much more efforts should be directed to develop useful catalysts in practical applications, in order to accelerate the progess of catalytic science and technology. (c) 2004 Elsevier B.V. All rights reserved.