A three electrode cell, constructed from PTFE and suitable for the application of controlled potential techniques to the study of electrode reactions in anhydrous hydrogen fluoride, is described. Steady state, cyclic voltammetric and pulse experiments have been used to study the fluorine evolution reaction at a platinum anode in anhydrous hydrogen fluoride at 273 K. It is shown that the reaction is autocatalytic and must involve oxidation of hydrogen fluoride molecules as well as fluoride ion; some detailed mechanisms are discussed. In view of the results presented, the rate of the fluorine evolution reaction is expected to be markedly dependent on the metal of the anode.