The author examines development through the cases of recognition by the common law of the doctrine that customary traditional native law and native title is recognized in colonies settled by the British, She concludes that at common law when the British Crown acquires sovereignty over a territory, pre-existing property rights are preserved and that a clear expression of intention to the contrary is necessary to extinguish them. She then notes a number of relevant United States and Canadian cases on the issue of the land rights of their aboriginal inhabitants. The decision in Millirrpum v. Nabalco Pty Ltd and the Commonwealth of Australia is subjected to critical scrutiny and it is concluded that the decision does not concur with the established common law. Finally, some of the legal problems involved in the recognition, by statute, of aboriginal land rights are discussed.