The objective of the project is the development of a decision support system for medical application, which is capable of analysing great volumes of X-ray pictures, detecting and identifying certain patterns in the X-ray pictures, and supporting the assessment of a wide range of medical screen tests. The project aims at the support of breast cancer screen tests with the emphasis on prevention. The work in the project is based on the achievements of the Hungarian and foreign research work and the medical and diagnostic experience related to the Hungarian cancer screen tests. The work uses the latest procedures of image and information processing including numeric and symbolic methods of image processing as well as neural networks and expert systems. The main goal of the system to give help for diagnosing mammographic images, because of the great similarities many elements of the system can be applied in other medical or technical diagnosis system e.g. analysis systems of CT and MR images, to detect special skin diseases (like melanoma), etc.