The Department of Health and Human Services, through the National Institutes of Health's Advanced Research Projects Agency for Health (ARPA-H), is soliciting proposals for the Imaging Data Exchange (INDEX) Program. This initiative aims to establish a sustainable platform that connects medical imaging data providers with developers and researchers, leveraging artificial intelligence and machine learning to enhance access to diverse medical imaging data and improve healthcare outcomes. The program is structured in two phases, focusing on business model refinement and system architecture design, with an emphasis on participant engagement and data quality. Interested parties can reach out to the INDEX Team at INDEX@arpa-h.gov for further information, and they are encouraged to review the attached Draft INDEX Innovative Solutions Opening (ISO) ARPA-H-SOL-25-112 for detailed requirements.