Glucagonoma syndrome is defined by the presence of an alpha-cell secreting tumour of the pancreas, elevated levels of glucagon, and a characteristic rash called necrolytic migratory erythema (NME). NME is usually a specific and often initial finding of glucagonoma syndrome, but it may occur in other settings unassociated with an alpha-cell pancreatic tumour (pseudoglucagonoma syndrome). Glucagonoma syndrome must be distinguished from pseudoglucagonoma syndrome. Prompt recognition of NME and subsequent workup for a glucagonoma can allow for an earlier diagnosis and enhance the chances of a favourable outcome. In particular, metastases occur late, so early recognition of glucagonoma syndrome before liver metastases can be life-saving. Surgical resection is the definitive treatment for glucagonoma syndrome, although chemotherapeutic agents, somatostatin analogues and radionuclide therapy are also employed. Herein, we offer an approach to workup after identifying NME and an update on its current treatment modalities.