F. Hollmann, I. W. C. E. Arends, D. Holtmann
When challenged by a difficult reduction reaction, a chemist should always also consider biocatalysis in synthesis planning. The inherent selectivity of enzymes has been known for many decades now and the practical applicability of biocatalysis has undergone dramatic improvements rendering it a true alternative to established chemocatalysis. In this contribution recent developments in the field of enzymatic reduction using whole cells and isolated enzymes are reviewed.