In this interview, David Zierler, Oral Historian for AIP, interviews Thomas Ramos, a physicist detailed to the Principal Associate Director for Weapons and Complex Integration at Lawrence Livermore Laboratory. Ramos discusses his current work writing an unclassified history of the weapons program at Livermore and the broad perspective this has given him on the Laboratory from the postwar era to the present. Ramos recounts his childhood in Brooklyn and his military enlistment after high school, which led to a tour in South Korea and then an order from West Point to pursue a master’s degree in nuclear physics. He discusses his graduate work at MIT and his research on bubble chamber experiments at Fermilab and Argonne before being ordered back to West Point to teach nuclear science. Ramos describes the opportunities leading to his appointment at Livermore four years later and his initial work on the X-ray laser program and the origins of the SDI program. He discusses the impact of the end of the Cold War on the Laboratory and the extent to which Reagan’s military spending accelerated the Soviet collapse. Ramos discusses his work at the Pentagon as a legislative affairs officer for the Assistant Secretary of Defense for Atomic Energy, and he explains Livermore’s increasing involvement in monitoring nuclear proliferation among terrorist groups and rogue states. He describes his transition to counterproliferation as a result of the end of nuclear testing at Livermore and the signification of the creation of the National Ignition Facility. Ramos describes the transition to his current work documenting Livermore’s history, and he reflect broadly at the end of the interview on how Livermore has adapted to evolving security threats over its long history.