The Formation of Globular Cluster Systems

I briefly review models for the formation of globular cluster systems, and summarize the observational properties (i.e., formation efficiencies, metallicity distributions, kinematics and ages) of the globular cluster systems of M87 and M49: two thoroughly studied elliptical galaxies. Many of the properties of the metal-poor clusters in these and other galaxies appear to be consistent with their formation in low-mass, proto-galactic fragments, as proposed by several different formation models. A number of outstanding questions concerning the formation of the metal-rich clusters in these galaxies are highlighted.