Quasi-realists face the challenge of providing a plausible analysis of acknowledgments of moral fallibility (e.g., I believe that lying is wrong, but I might be mistaken). This paper develops a new analysis of these acknowledgments, according to which they express moral uncertainty. After advertising the advantages of this analysis, I take up the question of how to understand moral uncertainty in expressivist terms. 1 The Challenge According to moral expressivism, the function of moral discourse is not to describe the world. Rather, it's to express desire-like attitudes. The main challenge for expressivism comes from the fact that moral discourse behaves much like descriptive discourse. Expressivists in the quasi-realist tradition seek to meet this challenge: they aim to reconcile expressivism with the realist trappings of moral language. Can this goal be achieved? In recent years, some authors have claimed that quasirealists are unable to account for acknowledgments of moral fallibility (Egan 2007; Köhler 2015). An example: Ava has just completed a term paper arguing that eating meat is morally wrong. She's con dent that her thesis is true. Still, she admits that it's possible that her thesis is mistaken. Ethics is hard, and she's aware that many smart people disagree with her. She is thus inclined to say things like: (1) a. I believe eating meat is wrong. b. But I might be mistaken. 1 How should we understand these acknowledgments, if moral beliefs are just desire-like states? Call this 'The Fallibility Challenge. ' 1 Beddor and Goldstein (2018) call these conjunctions 'concessive belief attributions' based on their resemblance to concessive knowledge attributions (sentences of the form, ⌜I know φ, but I might be mistaken⌝). Interestingly, while such CKAs are typically judged infelicitous, their belief-involving counterparts sound perfectly natural.