Sparkling wine produced by the traditional méthode champenoise requires a second in-bottle alcoholic fermentation of a base wine, leading to the sparkling wine. This second fermentation is followed by prolonged ageing in contact with yeast cells (lees). The autolysis of yeast occurs during the ageing of sparkling wines. During this process, the yeast releases different compounds that modify the organoleptic properties of the wine. The ageing period is required to give these wines their roundness and characteristic aroma and flavour. Autolysis products also influence the foaming properties of sparkling wine. Yeast autolysis is characterised by the hydrolysis of intracellular biopolymers by yeast enzymes activated after cell death. This results in the release of low molecular weight products. This article reviews the recent advances in understanding the yeast autolysis mechanism, the factors affecting autolysis, the nature of the released compounds and their effects on sparkling wine quality.