Gait electromyograms were obtained before and after tendon transfer, lengthening, or release in twenty-seven hemiplegic patients with equinus or equinovarus deformities. Abnormal patterns of muscle activity almost always were present preoperatively in the gastrocnemius, soleus, tibialis posterior, flexor hallucis longus, flexor digitorum longus, peroneus brevis, and tibialis anterior muscles in these patients. The surgical procedures to correct the foot deformities altered the gross patterns of activity of most of the muscles operated on by very little. Of particular importance to the surgeon was the finding that the pattern of activity of the muscles whose tendon was transferred, lengthened, or released was not altered after operation. This finding makes the preoperative gait electromyogram a useful means of determining the appropriate surgical plan, since it is an indication of the type of muscle activity to expect postoperatively.