MCAK is a kinesin-related motor protein that stimulates microtubule depolymerization. It localizes to centrosomes and nuclei during interphase, and to spindle poles and chromosome centromeres during mitosis. The cover figure shows a mixture of non-transfected and FLAGMCAK expressing cells that were stained for DNA (blue), FLAG-MCAK (green), and tubulin (red). MCAK overexpression increased the frequency of microtubule detachment from centrosomes, reduced the amount of microtubule polymer, and caused cells to exit from mitosis without cytokinesis, thereby producing large multinucleated cells with few and fragmented microtubules. The microtubule stabilizing drug paclitaxel was able to counteract the effects of MCAK overproduction. For details, see the article by Ganguly and colleagues on page 929.