This volume contains papers and short communications presented at the 12th Canadian Symposium on Catalysis. The aim of the meeting was to present an update on new and established areas of catalysis research being performed in industry, government and university laboratories. Topics covered relate mainly to resource processing, such as heavy oil and natural gas upgrading, and to environmental issues. Approximately half the papers are included in sections on hydrogenation, carbon-carbon bond formation and environmental issues. The remaining papers cover general topics and homogeneous reactions. Examples include studies of hydroprocessing catalysts, carbon-carbon bond formation via methane oxidative coupling and dimerization of olefins, homogeneous catalysts in polymerization and dimerization reactions, performance of pillared clays, metal-oxygen cluster compounds, zeolites and catalysts prepared by metal oxide vapour synthesis. Studies that address the environmental issues include wet-air oxidation, catalytic elimination of organics, oxidation reactions and catalyst regeneration. The book provides practitioners of catalysis with an update on a wide number of topics and will be particularly useful to those interested in an overview of current catalysis research activities. Specialists in the areas of hydrogenation, carbon-carbon bond formation, homogeneous catalysis and environmental issues will also find a valuable set of new data and interesting discussions on these topics.