Lena Daumanns's thesis describes structural and functional studies of the enzyme Glycerophosphodiesterase (GpdQ) from Enterobacter aerogenes. It also examines the properties of small mimics of this enzyme and related binuclear metallohydrolases such as the metallo-ß-lactamases to enhance our understanding of hydrolytic cleavage of important substrates like phosphoesters and ß-lactams. Overall, this project has led to a better understanding of the metal ion binding and active site structural features of the enzyme GpdQ. Daumann describes how she successfully immobilized phosphoesterase and related biomimetics on solid supports for potential applications in the area of bioremediation of organophosphate pesticides. Analysis shows that both the enzyme and biomimetics can be stored on the solid support without loss of activity. Furthermore, the author specroscopically and mechanistically characterized a number of Zn(II), Cd(II) and Co(II) complexes, some of which are among the most active biomimetics towards organophosphates reported to date. This thesis makes excellent reading for non-specialists because each chapter includes a short introduction section.