Necrotizing fasciitis (NF) is a highly aggressive infectious process, polymicrobial in nature, involving soft tissues with a high risk of rapid spread through superficial and deep fascial planes and muscular layers. Cervical NF is quite rare, is mostly of odontogenic origin, and may be complicated by descendant mediastinitis with a very high mortality rate. Systemic conditions impairing the patient's immune competence, such as diabetes, may play a predisposing role. An effective treatment strategy includes prompt diagnosis (clinical findings, local microbiological tests, blood culture and, if deemed necessary, histopathology), broad-spectrum antibiotic therapy as early as possible which should be later adjusted according to antibiogram results, stabilization of vital functions and, if possible, elimination/ treatment of predisposing factors. This paper describes a complex and emblematic case.