The reduction of 4,4’-bipyridyl (Bpy) has been studied at electrodeposited Ag electrodes in 0.1 M Na2SO4 using cyclic voltammetry and the electrochemical quartz crystal microbalance (EQCM). A film of reduced Bpy develops on the electrode surface at high negative potentials and its growth, development and removal can be observed and controlled by monitoring the mass responses. While the reduction process appears to be relatively straightforward, the re-oxidation process (as revealed in voltammograms) is complex and is generally not completed during a single cycle although full film removal can be accomplished by holding the potential for several minutes at -0.9 V. Cyclic voltammetric removal of thin films gives rise to a broad oxidation current stretching from -0.9 to 0.0 V, while similar removal of thicker films produces a noisy and uneven peak whose position is dependent on scan rate and potential and which concides with an increase in the rate of mass removal from the electrode surface. Possible processes leading to this behaviour are discussed.