Necrotizing fasciitis is a rare but life-threatening soft-tissue infection characterized by rapidly spreading inflammation and subsequent necrosis of the fascial planes and surrounding tissue. Infection typically follows trauma, although the inciting insult may be as minor as a scrape or an insect bite. Often caused by toxin-producing, virulent bacteria such as group A streptococcus and associated with severe systemic toxicity, necrotizing fasciitis is rapidly fatal unless diagnosed promptly and treated aggressively. Necrotizing fasciitis is often initially misdiagnosed as a more benign soft-tissue infection. The single most important variable influencing mortality is time to surgical débridement. Thus, a high degree of clinical suspicion is necessary to avert potentially disastrous consequences. Orthopaedic surgeons are often the first to evaluate patients with necrotizing fasciitis and as such must be aware of the presentation and management of this disease. Timely diagnosis, broad-spectrum antibiotic therapy, and aggressive surgical débridement of affected tissue are keys to the treatment of this serious, often life-threatening infection.