Microtubules are dynamic cytoskeletal polymers essential for intracellular transport, cell division, motility and differentiation. Microtubule dynamics and network remodeling are precisely regulated through combinatorial effects of myriad microtubule-associated proteins. Our research integrates biochemical in vitro reconstitution, single molecule light microscopy, quantitative image analysis, and computational modeling to uncover the molecular mechanisms underlying microtubule regulation. Because microtubules are a common target for chemotherapeutic agents and many of their regulatory proteins are implicated in cancer and neurodegenerative diseases, our mechanistic models provide not only fundamental biological insight but also bear critical medical relevance.