The book outlines the research results that allow us to forecast the production of metal phosphides based on interaction of polyphosphate and metal at heating. A number of conducted physical and chemical researches have determined the conditions for formation of phosphides of molecular composition: Fe3P, Fe2P, FeP, Ni3P, Ni5P2, Ni7P3, AIP, MoP, WP including alloys of eutectic composition of nickel under the condition of interaction in sodium cyclotiphosphate-metal system at heating. Distinctive features of polyphosphate-nickel and polyphosphate-chrome systems have been determined. Formation of phosphides only is typical for the former one, and formation of elemental phosphorous only is typical for the latter one. The fact of interaction of phosphides has been confirmed theoretically and experimentally. Phosphides as one of interim products of interaction take part in redox process and are oxidized to produce elemental phosphorous. It is intended for a wide range of specialists inthe field of non-organic synthesis, semiconductor materials science, metallurgists, chemists and process engineers in the phosphorous industry.