This essay explores the reception of ‘nuclear winter’ at the North Atlantic Treaty Organization (NATO). This response is paradigmatic of how scientific predictions can work as stimuli for science diplomacy activities, and either inflate or deflate these forecasts’ public resonance. Those who elaborated the theory in the early 1980s predicted that the environmental consequences of a future nuclear conflict would have been catastrophic; possibly rendering the earth uninhabitable and leading to the extinction of humankind. This prospect was particularly problematic for the Western defence alliance, since it was difficult to reconcile with the tenets of its nuclear posture, especially after the 1979 Dual Track decision, engendering concerns about the environmental catastrophe that the scientists predicted. Thus, NATO officials refrained from commenting on nuclear winter and its implications for the alliance’s deterrence doctrine for some time in an effort to minimize public criticism. Meanwhile, they progressively removed research on nuclear winter from the set of studies and scientific debates sponsored by NATO in the context of its science initiatives. In essence, NATO officials ‘traded’ the promotion of these problematic studies with that of others more amenable to the alliance’s diplomacy ambitions.