Carbon dioxide reduction is – in principle – attractive from several stand points. On one hand it is a very abundant substance in the atmosphere, and is a large contributor to the “green house effect”. If a synthetic route based on carbon dioxide could be found, not only humanity would have an almost inexhaustible source of raw material, but also the danger of global warming could be greatly reduced. Carbon dioxide is relatively easy to handle, and has very low toxicity. Its reduction products are quite varied according to the reaction condition, ranging from saturated hydrocarbons (with four or less carbon atoms ) and ethylene, to smalllinear alcohols (wits three or less carbon atoms ), carbon monoxide, formic acid, and oxalic acid. However, it is not clear at present whetherthese redactions can ever be made energetically and economically viable.