The possibilities for using fast-scan voltammetric detectors in flow injection analysis for individual and multicomponent determination of phenolic compounds are explored. A cyclic voltammetric unit for potential scans is connected to a three-electrode cell (carbon-paste working electrode, silver/silver chloride reference electrode and glassy-carbon auxiliary electrode). The resolution and hence the selectivity obtainabel from the electrode processes can be improved by derivatizing the current/potential recordings. Individual and simultaneous determinations of phenol, guaiacol and 2,4-dichlorophenol at levels lower than 1 μg ml −1 can be achieved by judicious selection of measurement potentials, and in worst cases, by use of simultaneous equations.