Purpose: The literature surrounding necrotising ulcerative gingivitis (NUG) is extensive, yet the rare nature of this disease means that there is a lack of good quality research available. This paper aims to scrutinise the literature and provide an up-to-date summary of the available information. Materials and Methods: A literature search was performed electronically using the Cochrane Library, Ovid Medline, Embase, PubMed Clinical Queries and Google Scholar. Keyword searches were carried out, utilising MeSH terms and free text. English language articles primarily were included, with key foreign language (French and German) articles included where possible from the 1900s to the present day. Results: Necrotising ulcerative gingivitis is a rare disease (prevalence 1%), with an acute, painful and destructive presentation. It is an opportunistic bacterial infection which is predominantly associated with spirochetes. Treatment of NUG must be provided on a case-by-case basis, tailored to what the individual can tolerate and the extent of the infection. Conclusion: Although there is low prevalence of NUG, its importance should not be underestimated as one of the most severe responses to the oral biofilm. Risk factors must be investigated and addressed. Treatment should consist of gentle superficial debridement, oral hygiene instruction and prescription of mouthwash and antibiotics in severe cases. Keywords: necrotising ulcerative gingivitis, NUG, trench mouth