4D is a unique programme working to create generally applicable solutions for four common diseases: arthritis, breast cancer, diabetes type 2 and cardiac failure. The programme is a collaboration between Karolinska Institutet and Stockholm County Council. The project will take collaboration between health care and research to a more practical level and an aim is to get new research results into clinical use faster. The project will also strengthen the patient participation in the care processes. We asked the programme leaders Ebba Carbonnier, Karolinska Institutet, and Christina Holmström, Stockholm County Council, about the programme and how the results are changing the health care and the clinical science.