The appearances, distribution, and direction of muscle in the unilateral cleft lip as indicated by electrical stimulation are described. The findings differ from those reported by Fata and associates in their dissections in that functionally the fibers do not appear to parallel the margin of the cleft. Based on these findings, a method of layer-by-layer, step-by-step closure of the unilateral cleft lip is described that attempts to split the orbicularis bulge and advance the lateral muscle into the philtrum to a position more nearly imitating the direction and extent of the muscle in a normal lip.