  A Monte Carlo program is presented that computes all four fermion processes
in $e^+ e^-$ annihilation. QED initial state corrections and QCD contributions
are included. Fermions are taken to be massless, allowing a very fast
evaluation of the matrix element. A systematic, modular and self-optimizing
strategy has been adopted for the Monte Carlo integration, that serves also as
an example for further event generators in high energy particle physics.
