The volume presents compounds of boron with nitrogen and updates the preceding supplement series. About half of the volume deals with boron nitride. Its importance in technical applications - more than 1500 publications have been analyzed in this area alone - has continued to increase in the last few years. New information is given on the preparation and the physical properties of the different modifications of boron nitride. Recent developments in the field of boron nitride for the production of semiconductors, ceramics, and fibrous materials and new boron nitride applications in nuclear technology are presented. The majority of the other boron-nitrogen compounds consists of aminoboranes, iminoboranes, and 3- to 8-membered heterocycles with emphasis on borazines. Special attention is devoted to B-N compounds which contain boron in a two-coordinated state.