A review. Herein, a comprehensive account of the state-of-the-art in the development of catalytic networks by combining metallic and biol. catalysts in aqueous media (the natural environment of enzymes) was presented. Among others, the combination of metal-catalyzed isomerizations, cycloadditions, hydrations, olefin metathesis, oxidations, C-C cross-coupling and hydrogenation reactions, with several biocatalyzed transformations of organic groups (enzymic reduction, epoxidation, halogenation or ester hydrolysis), were discussed.