The FLUKA radiation transport code and its use for space problems.

FLUKA is a multiparticle transport code capable of handling hadronic and electromagnetic showers up to very high energies (100 TeV), widely used for radioprotection and detector simulation studies. The physical models embedded into FLUKA are briefly described and their capabilities demonstrated against available experimental data. The complete modelling of cosmic ray showers in the earth atmosphere with FLUKA is also described, and its relevance for benchmarking the code for space-like environments discussed. Finally, the ongoing developments of the physical models of the code are presented and discussed.