  There is an intimate link between supermassive black hole (SMBH) mass (M) and
the stellar velocity dispersion (sigma) of the host bulge. This has a
fundamental impact on our understanding of galaxy and SMBH formation and
evolution. However, the scatter, slope and zero-point of the relation is a
subject of some debate. For any progress to be made on this relation, the
established values of M and sigma must be robust. Over 50% of current M
estimates have been made using the technique of stellar dynamics. However,
there is serious concern over this method that prompts their re-evaluation. In
addition, it is not clear how best to define sigma. The aim of the M-Sigma
Project is to use STIS long-slit spectroscopy, integral field spectroscopy and
the latest stellar models, to best estimate the values of M and sigma in as
many cases as possible. The project will determine the most appropriate
properties of the M-Sigma relation itself.
