Mitochondrial fission is the process by which mitochondria divide or segregate into two separate organelles. Mitochondrial fission is counteracted by mitochondrial fusion, where two mitochondria fuse together to form a larger structure.[1] Fusion can result in elongated mitochondrial networks. In healthy cells, mitochondrial fission and fusion are balanced, and disruptions to these processes are linked to various diseases. Mitochondria divide through binary fission, a process similar to that of prokaryotes, and this division is coordinated with the mitochondrial DNA replication process.[2] Some of the proteins involved in mitochondrial fission have been identified, and mutations in these proteins are associated with mitochondrial diseases.[3] Mitochondrial fission plays a significant role in the cellular stress response and is a key factor in apoptosis (programmed cell death).[4]