One of the main avenues for understanding the formation and evolution of galaxies is through studying their present day stellar populations. A new generation of population synthesis tools that we have been developing are now capable of extracting an unprecedented amount of information from high quality spectra of galaxies. In this talk I will present results from an ongoing program aimed at measuring the stellar initial mass function and detailed elemental abundance patterns of early-type galaxies over the interval 0<z<1. Current data suggest that the IMF varies systematically across the galaxy population, with implications both for star formation theory and the inferred dark matter content in the central regions of galaxies. Constraints on the abundances of the alpha elements, iron peak elements, and neutron capture elements offer the promise of reconstructing the detailed star formation histories of these now dormant galaxies. Measuring the evolution of these quantities through cosmic time will provide constraints on the assembly histories of galaxies and will open up a new era of `extragalactic chemical tagging'.
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