The purpose of this letter is to notify you that we will perform a quality control review of the FY 2024 single audit of the Parallax Advanced Research Corporation under Project No. D2025-DEV0SO-0148.000. We plan to begin the review in September 2025. The single audit is required by the Single Audit Act Amendments of 1996 (the Single Audit Act), Pub. L. No. 104-156, and 2 C.F.R. Part 200, “Uniform Administrative Requirements, Cost Principles, and Audit Requirements for Federal Awards” (Uniform Guidance). The Single Audit Act and Uniform Guidance require Federal agencies to assess the quality of single audits.