Mayhew joined the VCDNP in July 2018 as a Research Associate, focusing on issues of nuclear governance, including IAEA safeguards, as well as nuclear non-proliferation, nuclear verification, arm control, US-Russia relations, and the nexus between nuclear security and the peaceful uses of nuclear science and technology. A recent research publication includes a detailed, technical analysis of technologies that are not covered in the Model Additional Protocol’s Annexes but could still be considered significant in terms of safeguards planning, implementation and evaluation. He has also extensively studied the evolution of the implementation of safeguards at the State level. Some of his previous contributions to nuclear discourse have been published by Bulletin of the Atomic Scientists, Stiftung Entwicklung und Frieden, Arms Control Today, The Nonproliferation Review, and the Swedish Radiation Safety Authority. Mayhew is a Commissioner on the trilateral Young Deep Cuts Commission. 

Mayhew is a member of the first graduating class in the dual master’s degree programme in non-proliferation studies of the Middlebury Institute of International Studies at Monterey (MIIS) and the Moscow State Institute of International Relations (MGIMO).