Once, it would have been treated as a momentous achievement. Some considered it almost impossible. Now, many may be surprised and puzzled, because compliance with the Kyoto Protocol runs so counter to assumptions born of nurtured scepticism and/or misunderstandings. Still others may see it as irrelevant, as the world moved on at COP21 in Paris, or assume that somehow Parties cheated. But the analysis presented in this issue by Shishlov and his colleagues, documenting 100% compliance with the Kyoto Protocol’s first period commitments,1 is in reality none of the above. If not momentous, it is certainly not irrelevant, and it carries important lessons.