At present, in clinical environmental medicine there are no specific diagnostic methods available to demonstrate the existence of environment-related health disorders. A possible strategy to solve this problem may be the investigation of the etiological influence of genetic predisposition and environmental factors on human diseases. Therefore, at the University Hospital of Aachen, an interdisciplinary clinical research project was established, funded by the START programme of the Medical Faculty of the University of Aachen. In a first step, the complex etiological interaction of the so-called Multiple Chemical Sensitivity (MCS), polyposis nasi, hyper or hypo-sensitivity to odours, fragrance sensitisation, and atherosclerosis will be investigated. On the basis of the interdisciplinary clinical research project, it is intended that a Clinical Research Center for Environmental Medicine be established with the goal of developing a Germany-wide competence network.