This case demonstrates the rare but potentially fatal condition of synergistic necrotizing cellulitis of the head and neck. Although similar to necrotizing fasciitis, this is more extreme as it also destroys muscle. Peri-tonsillar abscess is a recognized cause, but has not previously been described in this country, however it is a condition commonly referred to otolaryngologists and awareness of the complication of synergistic necrotizing cellulitis is necessary to allow early recognition and prompt treatment. This should be by broad-spectrum intravenous antibiotics with extensive surgical debridement and drainage procedures repeated as necessary. Although this case had a successful outcome, many patients do not survive, particularly if treatment is delayed or inadequate.