This chapter aims to provide a selection of reactions that will illustrate the major mechanistic pathways. In the case of redox reactions for organic molecules, there is a large number of cases for which the mechanism has not been studied in any detail, or if it has, no consensus has arisen as to the true pathway. This is even true for such an important synthetic reaction as the Clemmensen reduction of a carbonyl group to a methylene unit by a zinc-mercury amalgam with concentrated HCl, that is, a typical metal/acid couple. Many redox reactions in organic chemistry involve single electron transfers, that is, are radical reactions. In some organic reactions the organic component of interest undergoes both oxidation and reduction, that is, there is a disproportionation reaction. In any reaction that involves the oxidation or reduction of an organic component, there must also be a corresponding reduction or oxidation of the other reagent, be it organic or inorganic.