This review provides an overview of glutathione (GSH), the most abundant low molecular weight thiol compound synthesized in cells, and its critical roles in protecting cells from oxidative damage and the toxicity of xenobiotic electrophiles. GSH plays a key role in maintaining redox homeostasis and regulating cellular processes such as apoptosis and cellular division. The review covers the sources of oxidants and electrophiles, the elimination of these reactive species by GSH, and methods for assessing GSH status in cells. It also discusses the synthesis and regulation of GSH, including the involvement of glutamate-cysteine ligase and glutathione peroxidase. Additionally, the therapeutic approaches for manipulating GSH content are addressed, highlighting the potential of GSH in treating diseases involving oxidative stress. The review emphasizes the importance of GSH in various cellular compartments and its role in protecting against oxidative damage, particularly in the lungs and liver.This review provides an overview of glutathione (GSH), the most abundant low molecular weight thiol compound synthesized in cells, and its critical roles in protecting cells from oxidative damage and the toxicity of xenobiotic electrophiles. GSH plays a key role in maintaining redox homeostasis and regulating cellular processes such as apoptosis and cellular division. The review covers the sources of oxidants and electrophiles, the elimination of these reactive species by GSH, and methods for assessing GSH status in cells. It also discusses the synthesis and regulation of GSH, including the involvement of glutamate-cysteine ligase and glutathione peroxidase. Additionally, the therapeutic approaches for manipulating GSH content are addressed, highlighting the potential of GSH in treating diseases involving oxidative stress. The review emphasizes the importance of GSH in various cellular compartments and its role in protecting against oxidative damage, particularly in the lungs and liver.