Enantiomerically pure substances become increasingly more important. For their synthesis hydrolytic enzymes are usefull reagents. Especially lipases and esterases are broad applicable due to their substrate specifity and their stereoselectiviy in the kinetic resolution of racemates or for asymmetric syntheses. Even small structural changes inhibit sufficient interactions between the substrate the enzyme (lock-and-key theory). In consequence, for each new substance, it is necessary to find a suitable enzyme for conversion. Usually, in for a classical approach, the chemoenzymatic hydrolysis is performed under pH-stat conditions. However, a direct application of this method to any problem is not possible at all, since for each individual substrate a substrate-specific enzyme has to be found. Thus, long reaction times and large amounts of substances result from this methodology. In order to minimize these expenditures, an enzymatic screening assay for microplates was developed. This highthroughput screening system (HTS) reduces not only the necessary time for finding suitable enzymes for a special synthetic problem but also the cost for eah individual assay. Recently developed test systems for the screening of enzyme-catalyzed enantioselective reactions were altered for their use in microplates. The corresponding detection systems were improved and the spectrum of the examinable substance classes was extended. In principle, both the alcohol part and the acid part of a racemic ester can be the chirale component. With these two methods the achirale component of the ester was used for the detection of the enzymatic reaction. Using a coupled enzymatic reaction the kinetics of the hydrolysis could be pursued and statements on the function of the examined enzymes could be made.