We first discuss recent progress in using the Milky Way globular cluster (GC) system as a 'test-bed' for properties derived from integrated spectra and stellar population models. Standard techniques may give rise to spuriously high alpha-element ratios at low metallicities. We then discuss evidence for early epoch (z ≥ 2) formation for most GCs in galaxies today. Recent accretions of GCs (and their host galaxy) make a small contribution but recent mergers form few if any new GCs in today’s elliptical galaxies. The early formation of metal-poor GCs and the bimodality seen in GC specific frequency requires a 'truncation' which may be due to reionization.
ESO astrophysics symposia: Globular clusters: guides to galaxies: Proceedings of the Joint ESO-FONDAP Workshop on Globular Clusters, Concepcion, Chile, 06-10 March 2006 / Markus Kissler-Patig (ed.), pp. 245-252