This research direction places ion-selective membranes under instrumental control by using a range of electrochmical excitation methods to perform work and impose well defined ion fluxes across the sample–membrane interface. Often the actual signal is acquired during an open circuit potential period to avoid contributions from the ohmic drop. These approaches allow one to perform chronopotentiometric measurements and hence to obtain complementary speciation information, to increase the sensitivity, operate selective membranes as ion pumps and achieve all-solid-state reference electrodes. This research was originally inspired by our earlier work on understanding spontaneous transmembrane ion fluxes and their role in dictating the detection limit of ion-selective electrodes.