Necrotising fasciitis is a rare but serious bacterial infection of the soft tissues. It usually affects immunocompromised individuals, and people with diabetes are at particular risk. The lesion often starts as a minor wound and rapidly progresses, becoming life-threatening if not recognised early and treated aggressively. The authors present a severe case of necrotising fasciitis of the right lower limb that led to a high-above-knee amputation with faecal diversion to prevent wound contamination. Split skin grafting was used to close the wound once it had granulated. Faecal diversion can be important in cases where there is inadequate skin cover close to the torso, as stumps can be contaminated with faecal organisms, resulting in sepsis and possibly death.