During telophase, the nuclear envelope (NE) reforms around daughter nuclei to 
ensure proper segregation of nuclear and cytoplasmic contents. NE reformation 
requires the coating of chromatin by membrane derived from the endoplasmic 
reticulum, and a subsequent annular fusion step to ensure that the formed 
envelope is sealed. How annular fusion is accomplished is unknown, but it is 
thought to involve the p97 AAA-ATPase complex and bears a topological 
equivalence to the membrane fusion event that occurs during the abscission phase 
of cytokinesis. Here we show that the endosomal sorting complex required for 
transport-III (ESCRT-III) machinery localizes to sites of annular fusion in the 
forming NE in human cells, and is necessary for proper post-mitotic 
nucleo-cytoplasmic compartmentalization. The ESCRT-III component charged 
multivesicular body protein 2A (CHMP2A) is directed to the forming NE through 
binding to CHMP4B, and provides an activity essential for NE reformation. 
Localization also requires the p97 complex member ubiquitin fusion and 
degradation 1 (UFD1). Our results describe a novel role for the ESCRT machinery 
in cell division and demonstrate a conservation of the machineries involved in 
topologically equivalent mitotic membrane remodelling events.