SUSY_FLAVOR: a computational tool for FCNC and CP-violating processes in the MSSM. We present SUSY_FLAVOR – a Fortran 77 program that calculates important leptonic and semi-leptonic low-energy observables in the general R-parity conserving MSSM. For a set of input MSSM parameters, the code gives predictions for the K ¯ 0 K 0 , D ¯D, B ¯ d B d and B ¯ s B s mixing parameters: B→X s γ, B s,d →l + l - , K L 0 →π 0 ν ¯ν and K + →π + ν ¯ν decay branching ratios; and the electric dipole moments of the leptons and the neutron. All these quantities are calculated at one-loop level (with some higher-order QCD corrections included) in the exact sfermion mass eigenbasis, without resorting to mass insertion approximations. The program can be obtained from