The author reviews recent research on the environment in which active nuclei reside, namely the dense stellar populations found in the centers of elliptical galaxies and spiral bulges. He discusses new developments concerning the structure and dynamics of nuclei, recent results on the age and chemical composition of nuclear populations, the possibility that important changes in the initial mass function occur in nuclei, limits which can be placed on recent star formation in old populations, and the detection of "submerged" active nuclei in outwardly normal galaxies. Emphasis is placed on problems for which space astronomy experiments are well suited.