Emma leads the Foundation's Nuclear Challenges program. Before Macarthur, Emma was at the Council on Foreign Relations, where she was a Stanton Nuclear Security Fellow. She has also worked as an advisor in Australia’s Department of the Prime Minister and Cabinet on national security and international affairs and as a public affairs officer at the Australian embassy in Washington, D.C.
She has a background in international security (Fletcher School of Law and Diplomacy, Tufts University, PhD and MALD; University of Melbourne, BA with honors. While completing her PhD, she was a fellow in the International Security Program and Project on Managing the Atom at Harvard University's Belfer Center for Science and International Affairs.
She serves on the advisory committee of N Square—a network of innovators working to end the nuclear threat. Emma was a 2014-2016 Emerging Leader at the Chicago Council on Global Affairs.