Katzmann has been a board director of the American Judicature Society, a public member of the Administrative Conference of the United States, and a vice-chair of the Committee on Government Organization and Separation of Powers of the ABA Section on Administrative Law and Regulatory Practice. He has also been a consultant to the Federal Courts Study Committee. He served as co-chair of the FTC transition team, and as special counsel to Senator Daniel Patrick Moynihan on the confirmation of Justice Ruth Bader Ginsburg. He has also been chair of the Section on Legislation of the Association of American Law Schools. Katzmann is a member of the Board of Trustees of the New York Public Library, the Board of Visitors of Georgetown University Law Center, the Board of Directors of the Institute of Judicial Administration of NYU, the advisory board of Roosevelt House of Hunter College, and a member of the National Board of Academic Advisors of the Rehnquist Center located in the James E. Rogers College of Law at the University of Arizona.