This essay deals with the problem of the status of colours, traditionally considered as the paradigmatic case of secondary qualities: do colours exist only as aspects of experience or are they real properties of objects, existing independently of human and animal perception? Recently, John Campbell has argued in favour of the simple view of colours, according to which colours are real properties of objects. I discuss the place of Campbell's position in a debated which was started by John Mackie and continued by John McDowell, and defend it from a criticism due to Michael Smith. I conclude that the simple view is a philosophically credible position. Subsequently, I consider an alleged contradiction between the simple view and semantic externalism pointed out by Jim Edwards. I suggest that a supporter of the simple view may consistently maintain semantic externalism, if she also accepts epistemological externalism about the canonical warrant of perceptual judgements.