During the last decade or so, the term bioelectrochemistry has been used to describe a variety of research endeavors involving electrochemical phenomena of biological systems. The phenomena grouped under this heading include such diverse areas as generation of potentials across membranes, the oxidation-reduction chemistry of macromolecules, and the application of electrochemistry to medical problems such as bone repair and tissue growth. Although this diversity has lead to fairly rapid growth, it has also resulted in difficulty in defining the field of bioelectrochemistry. The often quoted statement, "bioelectrochemistry is what bioelectrochemists do," does not allow one to identify the area as a viable scientific subdiscipline. It is partly the intent of this discussion to describe several areas of active research which, in the author's opinion, justifiably fall under the heading of bioelectrochemistry.