Necrotizing fasciitis is a devestating condition which has been recognized for several years. In North America a recent increase of cases has led to much media attention and public fear. Necrotizing fasciitis may occur as a consequence of infection with Streptococcus pyogenes or as a result of a polymicrobial synergistic infection caused by aerobic, anaerobic, gram positive and gram negative organisms, often in postoperative patients. Necrotizing fasciitis caused by Streptococcus pyogenes is mediated by superantigens. The management of necrotizing fasciitis requires a high index of suspicion for diagnosis followed by antimicrobial therapy and early surgical intervention. In cases caused by Streptococcus pyogenes with streptococcal toxic shock syndrome, intravenous immunoglobulin may be of benefit.