The relationship between the mass of the central supermassive
black hole (SMBH) and the bulge stellar velocity dispersion is fundamentally important
when considering galaxy formation and evolutionary scenarios. However, the
range in current estimates for the slope (and scatter) of the relation
lead to SMBH mass predictions that can vary by up to an order of magnitude.
This is unacceptable if trying to constrain galaxy formation and
evolutionary models. The M-Sigma project is currently working to remove these
uncertainties through a homogeneous and thorough study of both space and
ground-based data, and will produce the most accurate estimate of the
M-Sigma relation to date.