The 2nd International Symposium on Medical Data Analysis (ISMDA 2001) was the continuation of the successful ISMDA 2000, a conference held in Fra- furt, Germany, in September 2000. The ISMDA conferences were conceived to integrate interdisciplinary research from scienti?c ?elds such as statistics, s- nal processing, medical informatics, data mining, and biometrics for biomedical data analysis. A number of academic and professional people from those ?elds, including computer scientists, statisticians, physicians, engineers, and others, - alized that new approaches were needed to apply successfully all the traditional techniques, methods, and tools of data analysis to medicine. ISMDA 2001, as its predecessor, aimed to provide an international forum for sharing and exchanging original research ideas and practical development ex- riences. This year we broadened the scope of the conference, to included methods for image analysis and bioinformatics. Both are exciting scienti?c research ?elds and it was clear to the scienti?c committee that they had to be included in the areas of interest. Medicine has been one of the most di?cult application areas for computing. The number and importance of the di?erent issues involved suggests why many data analysis researchers ?nd the medical domain such a challenging ?eld. New interactive approaches are needed to solve these problems.