In addition to its use as a catalyst support, carbon can find application as a catalyst on its own, and a large number of applications of carbon as a catalyst, both in the liquid and in the gas phase, have been reported. Oxygen and nitrogen functional groups can perform as active sites, chemisorbing the reactants and forming surface intermediates of adequate strength. The role of surface chemistry in carbon catalysis is reviewed, with particular emphasis on those cases where the active sites have been properly identified, and useful activity correlations established. (C) 2009 Elsevier B.V. All rights reserved.