  The measurement of the hadronic cross-section in $e^+ e^-$ annihilation at
high luminosity factories using the radiative return method is motivated and
discussed. A Monte Carlo generator which simulates the radiative process $e^+
e^- \to \gamma+hadrons$ at the next-to-leading order accuracy is presented. The
analysis is then extended to the description of events with hard photons
radiated at very small angle.
