Charge transfer processes on liquid/liquid interfaces: The first century

Electrochemistry dealing with interfaces between two immiscible and ionically conductive solutions (ITIES) has been documented in literature already a hundred years ago. The work has only recently attracted a wider attention, with more modern treatment founded by the late Professor Ji?i Koryta. The principle of the work, its past and new trends in experimental electrochemistry, optical studies of the interface and recently emerging theoretical work are reviewed.