 Of course, even though the questions are distinct this does not entail that they should be treated wholly separately. One might think, for example, that X should mitigate but only if others pay at least some (or even all) of the costs, and that if sufficient financial support is not forthcoming then X is not obligated. With this in mind, it is appropriate to turn to the Burden-Sharing Question. A considerable literature has developed around the question of who should bear the costs of combating climate change.