This chapter explores the evidence for the existence of such new colour experiences and what their philosophical ramifications would be. I first define the notion of ‘novel colours’ and discuss why I think that this is the best name for such colours, rather than the numerous other names that they have sometimes been given in the literature. I then introduce the evidence and arguments for thinking that experiences as of novel colours exist, along with objections that people have had to (...) that evidence and to those arguments. To do so, I outline some facts about ordinary, non-novel colours before considering whether experiences as of novel colours, exist. Then I discuss the potentially significant ramifications the existence of novel colour experiences would have for theories of the metaphysics of colour, theories of the nature of colour experience, and for theories of the nature of perception more generally. (shrink)