To demonstrate the repercussions for Psychosomatic and Psychotherapeutic Medicine of the politically motivated decision to introduce case mix funding for inpatient treatment in Germany. Description of the development of an appropriate code list of procedures for Psychosomatic and Psychotherapeutic Medicine within the DRG-System. The code list OPS-301 which was valid in 2001 had no appropriate procedures for Psychosomatic and Psychotherapeutic Medicine. The scientific societies therefore had to develop possibilities for coding psychosomatic-psychotherapeutic procedures in the new OPS-301 2.1 which is valid since January 2002. This was achieved through the formulation of so-called complex codes, which are presented together with first coding tips. There are further tasks with risks and potential benefits which have to be accomplished after establishing these complex codes.