of interfacial reaction dynamics was developed. This theory clearly illuminates those conditions under which one- or two-dimensional diffusion (as opposed to three-dimensional diffusion seen in homogeneous reactions) can be expected to enhance the overall efficiency or reaction rate of a bimolecular reaction. Additionally, it was brought to light that in systems with many reactive sites on a single moiety, apparent kinetic cooperative effects can be expected even without site-site interactions. 2. A theoretical treatment for the interaction of a transmembrane electric field with the enzyme function of membrane bound proteins was formulated. The major effects were shown to be: a) For a constant (DC) transmembrane potential, the magnitude of the field strength determines the position of the conformational equilibrium. b) The energy contained in an externally modulated (AC) field can be transduced by an appropriate transmembrane protein and stored as either electrochemical potential or chemical bond energy. c) An enzyme complex located within a membrane can cause localized modulation of a metabolically generated DC transmembrane potential by the well-timed opening and closing of a channel. This allows for the understanding of the events of energy transduction in terms of classical enzyme mechanisms, where one part of the kinetic cycle occurs at a different electric field strength than the other part.