In this poster, we describe the Capillary Histology Imagery Visualization and Exploration (CHIVE) project that is developing new tools for studying the vascular system in the mouse brain. Our ultimate goal is to understand the micro-vascular architecture of the brain and its role in development and disease. The size and complexity of brain vasculature demands a new methodology for study. We are developing such a methodology for imaging and examining the micro-vasculature of the mouse brain. To study the vascular system in the brain, we need an imaging modality capable of seeing the capillaries, the smallest vessels that ultimately deliver oxygen and nutrients from the blood. We are interested in the patternings of these vessels throughout the brain. This requires an imaging modality capable of extremely high resolution: we must resolve individual capillaries that are a few microns wide, over the entire brain. At present, the only method capable of this resolution is histology and montage-microscopy: physically sectioning a specimen and imaging it under a light microscope. The histological process produces a unique dataset containing an immense amount of small details over a large volume. To make use of this data, we have needed to develop a new suite of tools for visualization and analysis. The result is a visualization system that allows a scientist to work with the large image sets that result from histology in a way that supports exploration and analysis that is tuned to the unusual features of the image sets. In the poster summarized in this abstract we will outline our protocol for data collection and the types of data it creates. We will describe how the features of the data lead to challenges for visualization and analysis. We will describe our preliminary system for working with the data, CHIVE, and describe how it responds to some of these challenges. We conclude by discussing some of the issues CHIVE does not presently address.