The latest radiology modalities are capable of producing several thousand high resolution images per examination. These images are used to construct volumes of data. This talk will present some recent results from the Center of Medical Image Science (CMIV) and the Norrköping Visualization and Interaction Studio (NVIS), both at Linköping University in Sweden. The first part of the talk will address the issue of data reduction and multi resolution representations for Level-of-Detail selection using the knowledge encoded in transfer functions. Knowledge encoding can also be used to obtain fuzzy classification of unsegmented data and it will be demonstrated how classification can be used to improve transfer function design and enhance features of interest. The second part of the talk will present methods for haptic (force feedback) interaction with volumetric data. New methods for the design and implementation of haptic modes for medical data will be presented and haptic feedback for time resolved volumes will be demonstrated. Throughout the presentation medical examples of volume rendering will be shown such as full body virtual autopsies using the presented methods.