The application of ISFETs has been focused up to now mainly on static measurements, comparable with the conventional way of applying ion-selective electrodes. The specific and unique properties of ISFETs, their small dimensions and very fast response, are not exploited explicitly in the case of static measurements. These features will, however, be explored more and more in the future, for example in flow-through and FIA systems as well as for ISFETs with an integrated coulometric actuator. In the latter case the ISFET is part of an active microchemical reactor. Similar systems may in the future contain bioactive materials, whose affinity to a biological analyte can be measured by means of stimulus-response experiments.