  The accurate knowledge of luminosity at e^+ e^- flavour factories requires
the precision calculation of the Bhabha cross section at large scattering
angles. In order to achieve a theoretical accuracy at the 0.1% level, the
relevant effect of QED radiative corrections is taken into account in the
framework of the Parton Shower method, which allows exclusive event generation.
On this scheme, a Monte Carlo event generator (BABAYAGA) is developed for data
analysis. To test the reliability of the approach, a benchmark calculation,
including exact O(alpha) corrections and higher-order leading logarithmic
contributions, is developed as well, implemented in a Monte Carlo integrator
(LABSPV) and compared in detail with the BABAYAGA predictions. The effect of
initial-state and final-state radiation, O(alpha) next-to-leading and
higher-order leading corrections is investigated and discussed in the presence
of realistic event selections. The theoretical precision of BABAYAGA is
estimated to be at the 0.5% level.
