Abstract. A new version of the Monte Carlo event generator Dpmjet is presented. It is a code system based on the Dual Parton Model and unifies all features of the Dtunuc-2, Dpmjet-II and Phojet1.12 event generators. Dpmjet-III allows the simulation of hadron-hadron, hadron-nucleus, nucleus-nucleus, photon-hadron, photonphoton and photon-nucleus interactions from a few GeV up to the highest cosmic ray energies.