Frege proposed that his Context Principle-which says that a word has meaning only in the context of a proposition-can be used to explain reference, both in general and to mathematical objects in particular. I develop a version of this proposal and outline answers to some important challenges to the resulting account of reference. I also relate my account of reference to Dagfinn Føllesdal's work on this issue and point out some features of my account that should be attractive to Føllesdal.