  We present abundance results from our Keck/HIRES observations of giants in
the Galactic Bulge. We confirm that the metallicity distribution of giants in
the low-reddening bulge field Baade's Window can be well-fit by a closed-box
enrichment model. We also confirm previous observations that find enhanced
[Mg/Fe], [Si/Fe] and [Ca/Fe] for all bulge giants, including those at
super-solar metallicities. However, we find that the [O/Fe] ratios of
metal-rich bulge dwarfs decrease with increasing metallicity, contrary to what
is expected if the enhancements of the other $\alpha$-elements is due to Type
II supernovae enrichment. We suggest that the decrease in oxygen production may
be due to mass loss in the pre-supernova evolution of metal-rich progenitors.
