Review on the use of whole-cell biocatalysts for the preparation of optically active hydroxyalkanephosphonates is presented. There are three general processes applied so far, namely the use of lipolytic organisms either for enantio selective hydrolysis of acyloxyalkanephosphonates or enantioselective acylation of hydroxyalkanephosphonates, the use of baker's yeast and other fungi for bioreduction of ketophosphonates and the use of bacteria and fungi for hydrolytic oxirane ring opening in substituted 1,2-epoxyethanephosphonates. (C) 2004 Elsevier B.V. All rights reserved.