Status and perspectives of photoinjector developments for high brightness beams

The development and reliable operation of high brightness electron sources are key issues for next generation short wavelength light sources and a future linear collider. This paper will concentrate on photo emission based injector developments for various projects which require individual solutions and face specific problems and challenges. A selective overview of developments and experimental results will be presented demonstrating that for a large parameter range dedicated photo injectors are able to fulfill the specific stringent requirements on beam quality and other beam parameters, e.g. the time structure of the beam.