  We review the intermediate coupling model for treating electronic
correlations in the cuprates. Spectral signatures of the intermediate coupling
scenario are identified and used to adduce that the cuprates fall in the
intermediate rather than the weak or the strong coupling limits. A robust,
`beyond LDA' framework for obtaining wide-ranging properties of the cuprates
via a GW-approximation based self-consistent self-energy correction for
incorporating correlation effects is delineated. In this way, doping and
temperature dependent spectra, from the undoped insulator to the overdoped
metal, in the normal as well as the superconducting state, with features of
both weak and strong coupling can be modeled in a material-specific manner with
very few parameters. Efficacy of the model is shown by considering available
spectroscopic data on electron and hole doped cuprates from angle-resolved
photoemission (ARPES), scanning tunneling microscopy/spectroscopy (STM/STS),
neutron scattering, inelastic light scattering, optical and other experiments.
Generalizations to treat systems with multiple correlated bands such as the
heavy-fermions, the ruthenates, and the actinides are discussed.
