The competence network paediatric oncology and haematology aims at improving the structure of paediatric oncology and haematology as a whole focussing in particular on the quality of clinical trials and study centres. This implicates the following measures: (1) Employment of research and trial assistants in order to improve the quality of documentation and study management in the participating hospitals. (2) Building up of an Internet portal to provide medical information for non-professionals, for patients and their families as well as for health professionals. (3) The project "Study Assistance" supports study centers during the process of writing and examining new treatment protocols so that they are in compliance with the Good Clinical Practice criteria, formal criteria and statutory provisions. It presently works on a structural standardisation of study protocols and case record forms in order to improve their usability. In addition, the working group "Quality Assurance in GPOH Study Centres" is engaged in developing a quality management system for study centers.