Tennis is a Foreign Affairs Officer in the Office of Strategic Stability and Deterrence in the Bureau of Arms Control, Verification, and Compliance at the U.S. Department of State working on the Asia and Indo-Pacific deterrence portfolio and next steps in U.S.-Russia arms control. She received a Masters in Public Affairs in International Relations and Public Affairs at the School of Public and International Affairs at Princeton University. In 2020 she received the Harold Rosenthal Fellowship in International Relations to work at CSIS and USAID. She was previously a Senior Research Assistant at the Center on U.S. and Europe at the Brookings Institution. She worked with Distinguished Scholar and former Deputy Secretary of State Strobe Talbott on his latest book project, as well as research and writing activities related to U.S. foreign policy, Russia and Eurasia, nuclear policy, and public affairs. She was a columnist for Bear Market Brief, a newsletter on Russian and Eurasian politics and economics, and was an emerging expert at the Forum on the Arms Trade. She was also a Class of 2018 CSIS PONI Nuclear Scholar.