The organization of intracellular components is dependent on the microtubule (MT) cytoskeleton, a network of rod-like filaments that form and disassemble on a rapid timescale. During cell division, MTs assemble into the mitotic spindle, where they generate forces that move chromosomes. MTs are also essential for cytokinesis, where they facilitate cleavage plane specification, constriction of the cleavage furrow, and abscission. The R. Ohi laboratory uses live cell imaging and reconstitution biochemistry to understand how MTs are organized and remodeled during cell division. Over the past 10 years, we have developed multiple lines of research to address unappreciated aspects of MT physiology during cell division. We defined a new mechanism that governs chromosome oscillations, discovered a new pathway that can drive assembly of the mitotic spindle, and demonstrated that actomyosin contractility controls MT stability during cytokinesis. We leverage this information to identify novel targets for chemotherapy, and screen for small molecule inhibitors of these protein factors. Our efforts are therefore focused on deepening our knowledge of a process fundamental to life, and on developing chemical matter that we hope will contribute to clinical management of diseases involving deregulated cell division, such as cancer.