Mary Anne Sullivan

Partner and Practice Area Leader in the Energy Regulatory Practice, Hogan Lovells US LLP


Ms. Mary Anne Sullivan is a partner for the energy regulatory practice at the law firm of Hogan Lovells US LLP. She has more than 25 years of experience as an energy lawyer. Sullivan has had direct involvement with virtually every segment of the energy industry and has represented clients on energy issues in administrative, regulatory, transactional, and litigation matters in both the private sector and the government. Her current practice primarily focuses on electricity regulatory matters and on transactional and regulatory matters involving climate change, nuclear and renewable energy, and advanced energy technologies. Chambers Global: The World’s Leading Lawyers has noted Sullivan’s “comprehensive understanding of the issues facing the energy industry.”

Sullivan served as General Counsel of the U.S. Department of Energy (DOE) from 1998 to 2001 and Deputy General Counsel for environment and nuclear programs from 1994 to 1998. She provided advice and counsel on electricity restructuring, the California electricity crisis, oil and gas policy, environmental compliance, global climate change, clean coal programs, the Northeast heating oil shortage, radioactive waste disposal, nuclear safety regulation, and privatization of uranium enrichment activities. Sullivan oversaw the legal support for the opening of the world’s first deep geologic disposal facility for radioactive waste and negotiated the first agreements with electric utilities regarding voluntary reductions of greenhouse gas emissions.

Sullivan was a member of Hogan & Hartson’s energy group from 1977 to 1993. She represented oil, gas, coal, and electricity interests before DOE, the U.S. Department of the Interior, the U.S. Department of Treasury, and the Federal Energy Regulatory Commission in related litigation.

Sullivan is a frequent public speaker and author of articles on a variety of energy and environmental law topics. She has testified before several congressional committees on various issues, has been a senior lecturer in law at Duke University Law School and a professorial lecturer in law at George Washington University Law School, and has served on the board of the Energy Bar Association.