ABSTRACT Conceptual engineering aims to improve our concepts. That's plausibly an extremely difficult thing to do. Should this make us sceptical of the idea that philosophers should try to do it? You might think so. Cappelen, in his Fixing Language: an Essay on Conceptual Engineering, thinks it shouldn't stop us – but his stated reasons are not really encouraging. In this paper, I say what I think Cappelen should have said, on the basis of a very rough cost-benefit analysis.