Necrotising soft tissue infections of the genitalia (NSTIG), commonly known as Fournier’s gangrene, is a rare but important surgical emergency associated with significant morbidity and mortality. It is estimated that every six hours of delay in surgical debridement leads to doubling of mortality rates. In this large cohort of 8098 patients diagnosed with NSTIG, 50% had presented with a symptomatically similar diagnosis in the previous three weeks, 64% of whom were diagnosed as non-infectious genital swellings, cellulitis and genital pain suggesting a missed opportunity. Only 16% saw a urologist and 46% received antibiotics. The study identified risk factors for missed diagnosis including morbid obesity and a history of recurrent urinary tract infections (UTIs), which the authors identify because of cognitive bias and difficulty in examination. Interestingly however, the 46% who were prescribed antibiotics still developed NSTIG; this suggests this is not a simple progression and underlines the fact that the pathophysiology of how cellulitis becomes a necrotising infection remains poorly understood.