"All scholarship is a collective endeavour, but this book, and the context in which it was completed, has taught us more about the necessities of collective intellectual work, and its material and emotional conditions, than we would have liked. The COVID-19 pandemic and lockdown came to our cities just as we completed the first draft of the book, but with a lot more work to do. Even before the coronavirus, we were conscious of the extent to which intellectual labour depends on other forms of labour, often unacknowledged and provided by others"--