This policy response reflects on how policy actions can shape the future of Ukraine’s science system and contribute to post-war recovery. It draws on several OECD indicators and highlights the challenge of “brain drain” as a structural problem that is aggravated by Russia’s war of aggression against Ukraine. It then makes the case for international co-ordination on talent circulation and exchange to prevent the irreversible loss of scientific expertise for key industries and the education of future generations in Ukraine. The policy response further argues that OECD countries can put in place new and strengthened scientific relationships with Ukraine, while also implementing temporary measures to assist both displaced scientists and those remaining in their posts under very challenging conditions.