Cytokinesis, the final step of cell division, has two crucial processes to achieve: equal sorting of cellular components between the daughter cells, and membrane ingression and closure. Both processes strongly rely on membrane components and properties. It is known that some lipids localize to the cleavage site and that membrane transport is required to relieve cortical tension during cytokinesis, which is necessary for the physical separation of cells. However, the precise role and mechanism of this essential membrane retrieval are unknown, as is the nature of the lipids and proteins involved, in part because it has been difficult to study the role of lipids in membrane organization due to a lack of appropriate tools. The goal of this multi-disciplinary proposal is to understand which lipids participate in cytokinesis and how cytokinesis and membrane transport interface. I will combine approaches from chemistry and chemical biology with cell biology and imaging to achieve this goal. My comprehensive and systematic investigation will provide new insights into the important question of how cells divide, which will not only be important for basic biology, but also for understanding how cell division is mis-regulated in diseases such as cancer.