The reaction of vanadium (V) derivatives with hydrogen peroxide or with alkyl hydroperoxides leads to peroxovanadium complexes which are effective and selective oxidants of organic and inorganic substrates either under stoichiometric or catalytic conditions. Examples of synthetically significant oxidations of various classes of organic compounds are reported together with details on the commonly accepted mechanisms operating. When possible a comparison is made between peroxovanadium complexes of other d(0) metal derivative, e.g. Ti(IV), Mo(VI) and W(VI).