Humerus fractures comprise 5% to 8% of all fractures. Nonunions are uncommon, but when they occur, they present a challenge to the orthopaedic surgeon and often are debilitating to patients. There are risk factors that may predispose patients to nonunion. Many methods of treating these nonunions have been described with varying degrees of success. We review the literature concerning the treatment of proximal, midshaft, and distal humeral nonunions and describe our treatment protocol based on the literature.