Don Ayer is Jones Day's most experienced Supreme Court lawyer, with 19 arguments before the Court and numerous arguments in other appellate courts. His experience covers subject areas ranging from criminal appeals to business torts to a wide range of constitutional and technical statutory and regulatory issues. He also has been lead counsel in 20 federal court jury trials.

After graduating from Stanford University and Harvard Law School, he clerked for Judge Malcolm R. Wilkey of the D.C. Circuit, and for Justice William H. Rehnquist. Before entering private practice in 1990, Don served for ten years in the United States Department of Justice as an Assistant U.S. Attorney in San Francisco, as United States Attorney in Sacramento, as Principal Deputy Solicitor General under Solicitor General Charles Fried, and as Deputy Attorney General. He has also served as president of the American Academy of Appellate Lawyers and of the Edward Coke Appellate Inn of Court, and currently teaches a course in Supreme Court Advocacy at Georgetown University Law Center and Duke University Law School.

Don is listed in Best Lawyers in America (appellate practice), Who's Who in America, Who's Who in the World, Chambers USA (National Appellate), and D.C. Magazine's Top 100 Lawyers in Washington, D.C. He is a member of the ALI, a Fellow of the American Bar Foundation, and Chairman of the Publications Committee of the Supreme Court Historical Society.