The Fortran code { SDECAY} is presented which calculates the decay widths and branching ratios of all supersymmetric particles in the Minimal Supersymmetric Standard Model, including higher order effects. The program incorporates the usual two-body decays of sfermions and gauginos as well as the three-body decay modes of charginos, neutralinos and gluinos. The three-body stop and sbottom decays are implemented as well and even the four-body stop decays are calculated. Moreover, the important loop-induced decays, the QCD corrections to the two-body widths involving strongly interacting particles and the dominant electroweak effects to all processes are evaluated.

PACS numbers: 12.60.Jv