The Fall 2021 Algebra and Number Theory Day, organized jointly by the University of Maryland and the Johns Hopkins University, will be held on Saturday, September 11, 2021 at Johns Hopkins University. The speakers will be David Ben-Zvi (University of Texas at Austin), Jayce Getz (Duke University), Ivan Loseu (Yale University), Mona Merling (University of Pennsylvania), and Carl Wang-Erickson (University of Pittsburgh).