Book excerpt: The rapid advance of computer capabilities over the last two decades has opened up a new field of numerical simulations in which detailed physical models can be made to represent the most complex processes. IAU Symposium 270 reviews a wide range of topics relevant to computer modeling in the fields of interstellar gas dynamics, star formation and galactic dynamics. It includes numerical techniques for modeling physical processes such as self-gravitating, radiative magnetohydrodynamics, as well as novel hardware options for acceleration and a view into the future of computation. Observations of interstellar gas and star formation are also reviewed. This book is ideal for graduate students and researchers in the field of numerical astrophysics.