She is Mexico's Secretary of Environment and Natural Resources since October 1, 2024, as part of President Claudia Sheinbaum Pardo's cabinet, whose administration prioritizes a human-centered ecological and environmental policy with a strong focus on sustainability and climate action.

Prior to this role, Ms. Bárcena served as Mexico’s Secretary of Foreign Affairs (2023-2024), where she spearheaded the development of the Mexican Human Mobility Model to address continental migration challenges. During her tenure, she also implemented a Feminist Foreign Policy, advancing gender equality and promoting parity within the Mexican Foreign Service. Previously, she was Mexico’s Ambassador to Chile (2022-2023), where she strengthened bilateral relations and fostered regional cooperation.

Her extensive international career includes serving as Executive Secretary of the Economic Commission for Latin America and the Caribbean (ECLAC) from 2008 to 2022, where she championed equality as a pillar of sustainable development. Earlier, she served as Chief and Deputy Chief of Staff to United Nations Secretary-General Kofi Annan (2006-2007) and as Under-Secretary-General for Management under Secretary-General Ban Ki-moon (2007-2008). She also held positions as Deputy Executive Secretary of ECLAC and Director of its Environment and Human Settlements Division.

Ms. Bárcena holds a Bachelor of Science degree in Biology from the National Autonomous University of Mexico (UNAM) and a Master’s degree in Public Administration from Harvard University. She has been honored with honorary doctorates from the University of Oslo, the University of Havana, and UNAM, as well as the 2013 International Relations Medal from the University of Anáhuac.