In the course of the revision of the International Classification of Mental Disorders (currently 10th revision, hence ICD-10), an international scientific partnership network group was founded by the World Health Organisation (Chair: N. Sartorius, Geneva) in order to review the international scientific evidence of putative significance for the revision of ICD-10 in different language areas.

In the course of this project we reviewed several areas of activity that may be of importance for the review process to develop ICD-11. First of all, general questions arise about how a psychiatric classification system should be organized. Will it still depend on classical psychopathological information with additional information from imaging, genetic and laboratory studies, and finally the patient history? An alternative approach is based on functional psychopathology be based on functional neural modules which represent functional activities of the human brain and their disturbances in mental disorders. Another area of debate is whether dimensions rather than categories shall lay a new foundation for the classification of mental disorders. A further issue arises when considering narrative elements of psychiatric history taking. In how far can or should such factors be integrated? All these questions are interwoven with the classical German contributions to psychiatric nosology by Kraepelin and Bleuler, which will be reassessed on the background of these current topics in revising ICD-10.