Abstract. Diffusion Tensor Imaging (DTI) is becoming a routine magnetic resonance technique to study white matter properties and alterations of fiber integrity due to pathology. The advanced MRI technique needs postprocessing by adequate image analysis and visualization tools. Whereas such tools have been developed at various research centers to drive methodological and clinical research, they have not become widely available as software freely distributed to the community. We have developed an integrated software package for efficient processing, fiber tracking, and interactive visualization of DTI data. This allows even nonexperts to explore DTI data and to obtain results that so far were exclusive to reseach teams with strong computer science support. This report describes our effort to combine common, well-established processing methods for DTI data, a recently developed powerful fiber tracking method and a modern image analysis and visualization environment into an integrated tool...