 Cell senescence is a process of irreversible cellular aging characterized by the accumulation of dysfunctional mitochondria and increased levels of reactive oxygen species. This leads to a decrease in oxidative phosphorylation efficiency and a corresponding increase in mitochondrial accumulation, which is known as mitophagy. The resulting senescence-associated mitochondrial dysfunction, SAMD, has been linked to the senescence-associated secretory phenotype, SASP, which is thought to contribute to age-related diseases such as cancer, cardiovascular disease, and neurodegeneration. Furthermore, SAMD has also been implicated in the development of obesity-related metabolic disorders. This article was authored by Victor I. Korolchuk, Satomi Miwa, Bernadette Carroll, and others.