The present invention provides methodology for the rapid discovery of catalytically-active species. In the method of the invention, gradient arrays of catalytic species to be evaluated are absorbed on or impregnated into a support material. Next, the supported array is placed in a single reactor and the desired chemical reaction is carried out. The reaction products stream is then analyzed for the existence of the desired reaction products. If desired reaction products are observed to be present, the support library is divided at least in one half and the reaction conducted again. This technique is then repeated until a single catalyst mixture (or multiple catalyst mixtures) is identified as having the desired catalytic activity.