Nilda Mesa teaches sustainability planning and content at the urban and global scale, incorporating design and creative techniques with policy planning and research on urban systems, public health and economic inclusion. She is the Director of the Urban Sustainability and Equity Planning Program with Columbia University's Center for Sustainable Urban Development (CSUD) in the Earth Institute. She is also a visiting professor at the Paris School of International Affairs at SciencesPo, and a visiting scholar at their Laboratory for Interdisciplinary Evaluation of Public Policies of Sciences Po (LIEPP). She has a long career in environment, energy and sustainability at the city, state, national and global levels, and now writes and presents extensively on the subjects of sustainable development and the UN SDGs, climate, energy, equity, resiliency and urban systems relating to them. She is a member of the Board of Directors of United Therapeutics (NASDAQ: UTHR), as well as several non-profit organizations.

She most recently served as Director of the NYC Mayor's Office of Sustainability. She directed and was the principal author and editor of OneNYC (2015), the city's long-term sustainability plan, which for the first time for a major US city tied environmental initiatives with economic development, equity and resilience. The innovative design process brought together over 70 city agencies, elected officials, a distinguished advisory board, and engaged stakeholders and city residents. She developed innovative programs including in climate, energy, sustainability, air quality, waste, green buildings, transportation, and public education. Internationally, she represented New York with the Obama Administration’s U.S.-China Climate Cities Initiative, with C40, and with the Under2 Coalition founded by California Governor Jerry Brown. Under her leadership, New York City received numerous awards for sustainability and climate initiatives.

Before joining Columbia, Mesa served in environmental leadership roles at the White House Council on Environmental Quality, the U.S. Air Force, the U.S. Environmental Protection Agency, and the California Attorney General's office. At the Air Force, she brokered negotiations on airspace and range expansions with tribal nations, state and federal resource agencies, local business communities, and environmental advocates. At EPA, she was Counsel to the NAFTA Task Force, serving as lead U.S. attorney in the implementation negotiations for the environmental side agreements, and on the U.S. NAFTA delegation. She also developed policy on international environmental negotiations.

Before joining SIPA, she founded Columbia University’s environmental stewardship office, one of the first at an university. She pioneered the development of sustainability theory and practice in urban settings, establishing energy reduction and climate goals, green building standards, improve recycling, programs that sent used equipment and supplies to nonprofits locally and in the global south, set up food recovery programs for local food banks and shelters, and worked on interdisciplinary initiatives bringing together scientists, researchers, faculty, students and operations teams. Under her leadership, the University began incorporating environmental justice considerations such as air quality into its practices. Columbia was recognized for its sustainability efforts and greenhouse gas emissions reductions.

She is a graduate of Harvard Law School and Northwestern University. She studied painting and sculpture at the Maryland Institute College of Art and the Art Students League. Her art may be found in the permanent collection of the 9/11 Memorial Museum, and she exhibited in New York, Canada and France. She was born in Cuba.