This SBIR Phase II effort will complete the development of a neuroinformatics system, Virtual Slice System (VSS), which will allow researchers to create images of complete microscopic specimens at the highest optical resolution, to store these very large (multi-GB) images in stand-alone or interoperable web-enabled databases, and to quantify, atlas, and share these images with researchers and colleagues. These very large image files, which we will refer to as virtual slides can be shared and viewed over the Internet and networks, and are viewed with functionality similar to that of a traditional microscope. Users have access to a single """"""""thumbnail"""""""" of the entire image, while also having access to any part of the slide at any resolution, up to the resolution of the light microscope used to acquire the images. Our innovative virtual slide viewer streams requested fields-of-view at the user-specified resolution; loading of images is extremely rapid since there is no need to download the entire image to the user's computer. Annotations overlaying the images can be made via a set of tools that will work in any standard Internet browser. The annotations will be stored with the images, without any alteration to the image file itself. These annotations can be used to delineate regions of interest, overlay text on the image, or can act as quantification tools. We will provide tools for researchers to perform morphometric analysis, stereological estimates, atlasing, and image-based analysis on virtual slides over Internet connections. The results of these analyses will be stored with the virtual slides, and will exist in free-form searchable databases. Multiple databases can be linked into loosely coupled federations of databases, allowing for ease of data sharing among researchers in remote locations. The system will provide new opportunities for researchers to collaborate, create virtual and remote laboratories, and archive collections on the Internet and intranets. ? ?