A multi-frequency view of blazars

This paper presents a number of recent results on blazar observations in several energy bands across the electromagnetic spectrum. It is showed that non-thermal extragalactic sources, like blazars and radio galaxies, will be discovered in large numbers by the next generation of microwave and high-energy (hard X-ray and gamma-ray) observatories. The implications for Simbol-X are addressed through specific simulations that make use of the latest expected performances of both Simbol-X detectors.