  \susy23 is a Monte-Carlo package for generating supersymmetric (SUSY)
processes at $e^+e^-$ colliders. Twenty-three types of SUSY processes with 2 or
3 final state particles at tree level are included in version 2.0. {\susy23}
addresses event simulation requirements at $e^+e^-$ colliders such as LEP.
Matrix elements are generated by GRACE with the helicity amplitude method for
processes involving massive fermions. The phase space integration of the matrix
element gives the total and differential cross sections, then unweighted events
are generated. Sparticle widths and decay branching ratios are calculated. Each
final state particle may then decay according to these probabilities. Spin
correlations are taken into account in the decays of sparticles. Corrections of
initial state radiation (ISR) are implemented in two ways, one is based on the
electron structure function formalism and the second uses the parton shower
algorithm called QEDPS. Parton shower and hadronization of the final quarks are
performed through an interface to JETSET.
