In the course of time, the chemical compositions of galaxies change due to heavy element enrichment by mass loss from stars (e.g., supernova and nova explosions, stellar winds). The stars produce the heavy elements by nuclear reactions in their interiors. Thus, the evolution of stars and that of the galaxies within which they reside are intimately connected. The Principal Investigators (PIs) propose a program of determining the chemical composition of the atmospheres of stars in our Galaxy using quantitative spectroscopy. Their fundamental aim is to address unresolved issues concerning the chemical evolution of the Galaxy, peculiar main sequence stars, and red giants and their nuclear reactions. The proposed program is a continuation of past work supported by NSF.