The National Institutes of Health (NIH) is offering a funding opportunity for the establishment of Diagnostic Centers of Excellence (DCoEs) through the Diagnostic Centers of Excellence (X01 Clinical Trial Not Allowed) program, identified by NOFO number PAR-23-171. This initiative aims to support investigators in accessing resources from a Data Management Coordinating Center as part of the Undiagnosed Diseases Network, focusing on diagnosing complex and rare diseases that remain unresolved despite previous evaluations. While no direct funding is provided, successful applicants will gain essential infrastructure and clinical research support, with a requirement to enroll a minimum of five participants annually and share relevant data within a collaborative governance framework. Interested applicants must submit their proposals by May 15, 2025, and can find additional information and application guidelines at NIH Grants. For inquiries, contact NIH Grants Information at grantsinfo@nih.gov.