The application of electrochemical techniques to investigate interfacial processes outside the traditional boundaries of electrochemistry is discussed. By drawing on the well-established merits and principles of electrochemical methods, it is shown how a wide range of processes at electrically insulating interfaces can be investigated quantitatively under conditions where: (i) mass transport and surface kinetic effects can be separated; (ii) interfacial reactive fluxes can be measured and interpreted in terms of interfacial speciation; (iii) the influence of surface structure can be explored. The relative attributes of the channel flow method with electrochemical detection, the channel stopped flow method, microelectrochemical measurements at expanding droplets, scanning electrochemical microscopy and integrated electrochemical-atomic force microscopy are assessed as probes of physicochemical phenomena at liquid/solid, liquid/liquid and liquid/gas interfaces.