Within the framework of international trade liberalization which has given rise to considerable thought about the fundamental contribution of cultural diversity to sustainable development, we explore the upholding of the educational rights of recognized linguistic minorities and of the aboriginal and treaty rights of First Nations under the 'Constitution Act, 1982'. We examine these rights in the light of relevant judgments of the Supreme Court of Canada in order to confirm our initial hypothesis that the highest court in the land can show governments here and abroad the steps to take to ensure that the cultural rights specific to some communities and the citizenship common to the population as a whole can coexist in a free and democratic nation. Our analysis shows that, while relying on the historical, equality and cultural-based justification of the existence of these rights, the Court favours an approach centred on three fundamental principles: the duty of the State to act equitably in the "best interest" of cultural minorities through a flexible approach to the interpretation of established rights; a fair participation in the management of and access to resources by minority groups; and finally, the fostering of social cohesion in order for unity in diversity to be maintained through a reconciliation of existing rights which must be achieved, first and foremost, by political discussion aimed at finding durable solutions. From a cultural sustainable development perspective, the specific cultural rights of minority groups must thus favour a common citizenship within a context of respect for cultural diversity, while still being compatible with and promoting the values of a liberal democracy.