Title: Formation of Stars and Stellar Clusters in a Turbulent Interstellar Medium Andreas Burkert University of Munich Abstract: Star formation is one of the most important unsolved problems of astrophysics. I will summarize recent models of star formation in turbulent gas clouds and present new simulations of the formation of stellar clusters including energetic feedback processes that in the late phases destroy the surrounding molecular cloud. The conditions that lead to the formation of bound, dense star and globular clusters or to diffuse open clusters will be analysed. Evidence will be discussed that star formation is an initial condition problem and related to the question of molecular cloud formation. This leads to the conclusion that the small-scale process of star formation is intimately coupled with the large-scale dynamics and evolution of galaxies. The conditions are discussed that allow star formation in a galaxy to proceed in a low, self-regulated mode or that trigger runaway star bursts.