Professor Freeman is a top expert on energy and climate change and has written extensively about the history of U.S. energy and climate law. Her work in this area focuses on strategies to reduce greenhouse gas emissions and limit dependence on fossil fuels. She teaches and writes about energy and climate change, particularly the need to transition to a more sustainable energy system and to promote renewable energy. Freeman founded and is the Director of the Environmental and Energy Law program at Harvard Law School, which works to remove legal obstacles to a more sustainable energy system and to adapt legal and regulatory strategies to promote clean energy, to ensure that global temperatures do not rise beyond manageable levels. Her work at Harvard University’s new Salata Institute focuses on the intersection of energy and climate change. She is involved in several cross-university projects aimed at reducing greenhouse gas emissions, stabilizing global temperatures, and advancing more sustainable energy.