Unlike conceptual analysis, conceptual engineering does not aim to identify the content that our current concepts do have, but the content which these concepts should have. For this method to show the results that its practitioners typically aim for, being able to change meanings seems to be a crucial presupposition. However, certain branches of semantic externalism raise doubts about whether this presupposition can be met. To the extent that meanings are determined by external factors such as causal histories or microphysical structures, it seems that they cannot be changed intentionally. This paper gives an extended discussion of this ‘externalist challenge’. Pace Herman Cappelen’s recent take on this issue, it argues that the viability of conceptual engineering crucially depends on our ability to bring about meaning change. Furthermore, it argues that, contrary to first appearance, causal theories of reference do allow for a sufficient degree of meaning control. To this purpose, it argues that there is a sense of what is called ‘collective long-range control’, and that popular versions of the causal theory of reference imply that people have this kind of control over meanings.