  We discuss the process of adiabatic growth of central black holes in the
presence of a stationary, pre-existing distribution of collisionless stars.
Within the limitations of the assumptions, the resulting models make robust
physical predictions for the presence of a central cusp in the stellar and dark
matter density, a Keplerian rise in the velocity dispersion, and a significant
tangential polarization of the velocity tensor. New generations of numerical
models have confirmed and extended previous results, permit the study of
axisymmetric and triaxial systems, and promise new insight into the dynamics of
the central regions of galaxies. These studies enable detailed comparisons with
observations, further our understanding on the fueling processes for AGNs and
quiescent black holes, and help elucidate the secular evolution of the inner
regions and spheroids of galaxies.
