? ? The goal of the International Mouse Strain Resource (IMSR) is to facilitate access to mouse resources and mouse models of human disease that are used for basic and translational research. The unique and pivotal role of IMSR is in unifying information about mouse resource holdings worldwide, including inbred, mutant, and genetically engineered mice maintained as breeding stock, cryopreserved embryos and gametes, and ES (embryonic stem) cell lines. At the IMSR website (www.imsr.org), users can search for mouse resources, locate strains for their research, learn details about a strain, contact a repository for ordering mice, and link to phenotype and disease model descriptions. Here, we propose to further develop the IMSR infrastructure and user interface: (1) to better represent gene trapped and targeted ES cell lines that will become a major resource type in the developing large-scale gene knockout projects; (2) to expand IMSR representation such that resources created using other new and developing technologies can be easily incorporated into IMSR; (3) to improve automation and reporting functions of the IMSR; (4) to enhance web content to provide user access to additional data; and (5) to improve web usability for translational and clinical researchers less familiar with mouse models. We will also support the critical IMSR curation activities to ensure that the data in IMSR continue to improve and are consistent with scientific community standards. This includes development of curation tools to enhance the ability of IMSR to utilize data from other online resources. It is imperative at this time, when many new unique mouse resources are rapidly expanding and new repositories are being established, that IMSR grow and change with the scientific community's progress and enhance its infrastructure to be positioned to fully support these new resource needs. Relevance to Public Health: Virtually all advances in human medicine rely on the use of animal models, and chief among these model systems is the laboratory mouse. The International Mouse Strain Resource (IMSR) is a publicly accessible online resource that assists the scientific community in finding information about worldwide mouse resources, locating the repositories from which they can be obtained, and ordering needed resources. Through IMSR users also can link to phenotype and disease model descriptions to evaluate and select the most appropriate experimental model for their research. The proposed enhancements to IMSR will improve access to thousands of new valuable mouse resources by enabling their inclusion as they are developed, by adding repository sites with unique mouse resource holdings, and by enhancing information content available to the user online. ? ? ?