Variables important in the synthesis of supported metal catalysts using the sol-gel method are reviewed. Potential applications of these materials are presented with emphasis on : thermally resistant materials, catalysts with low deactivation rates, high surface area materials, catalytic membrane reactors and high surface area superacid materials. Emphasis is on synthesis conditions including the control of variables which enable the preparation of well defined pore size distributions, The reforming reactions of n-hexane are used as a basis for comparison between catalysts.