Motors and MAPs collaborate to size up microtubules.

Midzone microtubules keep chromosomes apart after segregation and provide a platform for cytokinesis factors. Reporting recently in Cell, Subramanian et al. (2013) describe how the motor protein kinesin-4 and the microtubule-associated protein PRC1 work together to mark microtubule ends for incorporation into the midzone in a length-dependent manner.