Abstract: Photon-based radiosurgery is widely used for treating local and regional tumors. The key to improving the quality of radiosurgery is to increase the dose falloff rate from high dose regions inside the tumor to low dose regions of nearby healthy tissues and structures. Dynamic photon painting (DPP) further increases dose falloff rate by treating a target by moving a beam source along a dynamic trajectory, where the speed, direction and even dose rate of the beam source change constantly during irradiation. DPP creates dose gradient that rivals proton Bragg Peak and outperforms Gamma Knife® radiosurgery.