  The investigation of events with Initial State Radiation (ISR) and subsequent
Radiative Return has become an impressively successful and guiding tool in low
and intermediate energy hadron physics with electron positron colliders: it
allows to measure hadronic cross sections and the ratio R from threshold up to
the maximum energy of the colliders running at fixed energy, to clarify
reaction mechanisms and reveal substructures (intermediate states and their
decay mechanisms) and to search for new highly excited mesonic states with
J^{PC} = 1^{--}. While being discussed since the sixties-seventies ISR became a
powerful tool for experimentalists only with the development of EVA-PHOKHARA, a
Monte Carlo generator developed over almost 10 years, while increasing its
complexity, which is user friendly, flexible and easy to implement into the
software of existing detectors.
