More than 80 years ago, Otto Warburg described the phenomenon whereby cancer cells avidly take up glucose and produce lactic acid under aerobic conditions, a process subsequently referred to as the Warburg effect or aerobic glycolysis. The exact molecular mechanisms underlying cancers reliance on glycolysis remains unclear, but is likely a combination of an epigenetic response to the hypoxic tumour environment in combination with direct oncogenic stimulation. The aim of the current manuscript is to review the normal process of glycolysis and highlight the alterations that occur with malignant transformation, to consider the potential advantages of glycolytic respiration for cancer cell survival, and finally to explore areas where altered glucose metabolism can be exploited for clinical benefit.