The goal of this proposal is to disseminate high resolution large volume serial section electron microscopy data to neuroscientists. Using our electron microscopy facility, we will provide user training on the use of these new technologies and provide access to our specialized facilities so that they may generate permanent ultrathin sections and create data sets amenable for neural circuit analysis or neural and glial cell type analysis. We will make minor improvements in our software to increase the scale and efficiency of user data production to meet the needs of a user community that are inexperienced in these approaches. This project addresses compelling needs of neuroscience researchers who work on the first high priority goal of the BRAIN 2025 report: ?Mapping the Structure and Components of Circuits? by providing them access to tools that are otherwise unavailable or impractical in their current form.