  The origin of the X-ray background spectral intensity has been a long
standing problem in high energy astrophysics research. Deep X-ray surveys
carried out with ROSAT and ASCA combined with the broad band spectral results
of Ginga and BeppoSAX satellites strongly support the hypothesis that the bulk
of the X-ray background is due to the integrated contribution of discrete
sources (mainly AGNs). At higher energies the unexpected findings of the
Compton Gamma Ray Observatory indicate that also the gamma-ray background is
likely to be due to AGNs. I will discuss AGN--based models for the high energy
backgrounds and how future observations will improve our understanding of the X
and gamma-ray backgrounds and of the physics and evolution of AGNs.
