Twenty-four hands of twenty carefully selected patients with injury to the cervical spinal cord and paralysis of the upper extremities had better grasp after tendon transfers. Grouping the patients with these injuries according to the presence of certain voluntarily functioning muscles was helpful in planning treatment. When a proper program of positioning, exercises, and splinting was carried out, most quadriplegic patients achieved useful grasp by means of the tenodesis effect of the automatic hand. Voluntary wrist extension was the key to good grasp with or without surgery. If effective prehension was not acquired after a rehabilitation program had been completed, and improvement in neural function had ceased, transferring suitable motors improved grasp by providing finger flexion and thumb opposition.