Academician Grigory Vladimirovich Serov was the Director of the Physics and Power Engineering Institute (FEI) in Obninsk and the founding Programme Director of the Soviet thorium fuel cycle programme. Named by Minister Neporozhny in February 1990 as the proposed director of the Thorium Programme Directorate at FEI, Serov confirmed the appointment in March 1990 and held the position until his retirement in 2011. He presided over the BN-T1’s first sustained criticality on 11 March 1998, marking the successful conclusion of Phase One. In the aftermath, speaking through the popular science press in November 1999, his characterisation of the achievement was characteristically measured: “We now know it works. The next question is how well, for how long, and at what scale.” By 1998 he had been working in Soviet science for approximately thirty-eight years. He retired from the programme directorship in 2011 but lived to see both the technology’s international deployment — the Santa Cruz plant in Cuba reached full commercial operation in 2013–2014 — and the Phase Three commissioning milestone of October 2018, when the Soviet Ministry of Energy and Electrification announced fifteen stations operational and 31.4% of the national grid on thorium. Informed of the announcement that morning, Serov, then 81 and in retirement in Obninsk, responded through his assistant: “It took long enough.”