Volumetric image display and analysis techniques have been under development to support x-ray computed tomographic (CT) imaging of the heart and lungs since the mid 1970s when investigators began to understand the image analysis requirements for the Dynamic Spatial Reconstructor. With the spread of Imatron's C-100 scanners (Imatron, South San Francisco, CA) around the world along with the development of slower helical scanners that generate volumetric information, there is an increased interest in the use of volume visualization and analysis tools to study the cardiopulmonary system. An historic overview of the development of such volume visualization for x-ray CT scanning is given along with a discussion of techniques for data acquisition, volumetric display, and image quantitation. We further show throughout the discussion how the integration of tools into a comprehensive image display and analysis software package (the tool box) enhances the utility of the individual tools. An example of such a tool box is given in a discussion of an X Windows-based package dubbed VIDA.