GSH itself is a critical factor in maintaining the cellular redox balance and has been demonstrated to be involved in regulation of cell signalling and repair pathways. Enhanced expression of various enzymes involved in GSH metabolism, including glutathione peroxidases, γ-glutamyl cysteinyl synthetase (γ-GCS), glutathione S-transferases (GST) and membrane proteins belonging to the ATP-binding cassette family, such as the multidrug resistance associated protein, have all been demonstrated to play a prominent role in cellular resistance towards oxidative stress. This review stresses the fact that a co-ordinate interplay between these systems is essential for efficient protection against oxidative stress.