I present integrated-light (IL) abundance measurements of 45 Local Group globular clusters. Abundances were determined from fitting of synthesized model spectra, for the first time including non-LTE corrections to the IL abundances for many individual elements. Overall, metal-poor GCs in different galaxies exhibit remarkably uniform abundance patterns of alpha-, iron-peak, and neutron-capture elements, suggesting that the parent galaxies experienced relatively similar early enrichment histories. At metallicities [Fe/H]>-1.5, some differences emerge, with GCs in dwarfs typically being less alpha-enhanced. A serendipitous result is the discovery of an extremely metal-poor, massive GC in M31 ([Fe/H]=-2.9), well below the previously suspected GC "metallicity floor" at [Fe/H]~-2.5. The high mass of this cluster is in tension with commonly assumed mass-metallicity relations for galaxies at high redshift, and may therefore provide a valuable datum for constraining such relations.
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