In this article, I test the claims of the UK government and universities that the Prevent programme aims to create a safe space for the discussion of "extremist" ideas in universities. I do this by comparing the main elements of the Prevent duty that has been imposed on universities with those of safe spaces as imagined by student campaigners and some educational writers. I conclude that, while there are manifest and significant differences in the harms that the two strategies aim to prevent, and in the sources, nature and targets of the coercion that the two strategies entail, their overall form and the underlying assumptions that rationalise them are shared. I consider some implications of their differences and of their shared characteristics for the critics of the two strategies.