  Studies of galactic circumnuclear environments is important to our
understanding of the feeding and feedback of the central super-massive black
hole and in turn the global evolution of the host galaxy. We present an
observational overview of the circumnuclear environment in M31 and a tentative
understanding of its regulation. Notes on selected open issues, as well as on a
comparison with the Galactic Center and other extragalactic circumnuclear
environments, are also presented.
