Title: Dispersal of Protoplanetary Disks Author: Uma Gorti Abstract: Circumstellar disks originate during star formation and evolve rapidly, to perhaps form planetary systems before they disperse. I will discuss the evolution of disks in the context of recent theoretical models, with a special focus on their gas content. Disk dispersal mechanisms, mainly viscous evolution and photoevaporation, will be described and theoretical models will be compared with observations to summarize our current understanding of how disks evolve and the constraints posed for planet formation.