There is mounting evidence that disk accretion plays a dominant role in the mass growth of super-massive black holes. I will start my talk with a discussion of how the physics of accretion disks in the vicinity of (super-massive) black holes differs from normal (Shakura-Sunyaev-type) accretion disks. In the second part, I will present results of time-dependent numerical models of the accretion-driven growth of individual black holes. And in the final part, I will show first results of an ongoing project modeling the evolution of the population of (active) galactic centers from large to small redshifts.
