Mortality from battlefield wounds has historically declined, thanks to better surgical management, faster transport of casualties, and improved antibiotics. Today, one of the major challenges facing U.S. military caregivers is the presence of multidrug-resistant organisms in orthopaedic extremity wounds. The most frequently identified resistant strains of bacteria are Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter calcoaceticus-baumannii complex. Overuse of broad-spectrum antibiotics may be an important factor in building resistant strains. Acinetobacter infections appear to hospital-acquired and not from an initial colonization of the injury. More research is required to give military physicians the tools they require to reduce the infection rate and defeat multidrug-resistant organisms.