A new model for binocular processing is described. (i) In the bilateral either-eye channel, summation of the excitatory monocular responses is preceded by partial, reciprocal inhibition between each eye's responses. (ii) In the fused channel, the response is binocular, purely excitatory, multiplicative. (iii) The net binocular response of the system is a sum of the outputs of (i) and (ii). The model contains no independent monocular contributions to the net binocular response. All stimuli on corresponding retinal loci are processed in the either-eye channel; in addition, the fused channel responds to stimuli that are near 0-phase interocularly. The model is sufficiently general to account for binocular performance at the differential luminance threshold and in suprathreshold contrast matching, and it also offers a novel explanation for interocular transfer of adaptation. Plausibility of the model is briefly considered with regard to visual neurophysiology.