The first volume of "The Chemistry of the Hydrazo, Azo and Azoxy Groups" was published in 1975 in two parts, and the present book is the second volume of this publication. Since 1975 three supplementary volumes dealing with the chemistry of double-bonded functional groups were also published in the Series and these volumes contain much material on the chemistry of azoxy compounds. Several subjects were omitted from the original volume in 1975. These omissions have been corrected in the present volume, which contains chapters on "Detection, identification and determination," on NMR, on ESR, on PES, on pharmacology and toxicology, and also on safety and environmental factors.