  Blazars, the extreme family of AGN, can be strong gamma-ray emitters and
constitute the largest fraction of identified point sources of EGRET. The next
Gamma-ray Large Area Space Telescope (GLAST) is a high energy (30MeV-300GeV)
gamma-ray astronomy mission, planned for launch at the end of 2006. GLAST
performances will allow to detect few thousands of gamma-ray blazars, with a
broad band coverage and temporal resolution, also in quiescent emission phases,
providing probably many answers about these sources.
