Necrotizing fasciitis is a limb- and life-threatening soft-tissue infection. Eighteen patients with necrotizing fasciitis of the extremities were reviewed. These infections occurred most commonly after minor trauma. Associated chronic debilitating diseases were present in 13 patients. All but two infections were polymicrobial. The overall mortality rate was 33%. Death was caused by persistent wound sepsis in three and systemic septic complications in spite of apparent local infection control in three. At the admission physical examination the condition may resemble a benign, low-grade cellulitis. Three of four patients died because of a delay in surgical debridement for more than 24 hours after admission. Multiple radial debridements of the involved skin, fat, and fascia are essential to control progressive necrosis. Our results suggest that early diagnosis and prompt surgical debridement of necrotizing fasciitis are essential for survival.