A goal of the Biomedical Informatics Research Network (BIRN) project sponsored by NCRR/NIH is to develop a multiinstitution information management system for Neurosciences, where each participating institution produces a database of their experimental or computationally derived data, and a mediator module performs semantic integration over the databases to enable neuroscientists to perform analyses that could not be executed from any single institution’s data. This demonstration paper briefly describes the current capabilities of Metropolis-II, the information integration system for BIRN.