The High Court of Australia continued to develop its broad interpretation of the external affairs power of the Commonwealth Constitution (section 51(xxix)) in the Koowarta case in 1982. The arguments of the justices and the implications of the decision for the governance of schooling in the Australian federal system — given the several international conventions which have education as a central concern or allude to it and to which Australia is a signatory — are explored in this paper. The broad interpretation oy the Court both gives the Commonwealth powers over education not hitherto held and negates the commonly held view that education is a States’ right. The Court's decision, in which education is incidentally mentioned as being affected by the broad interpretation, necessarily involves the Commonwealth in the governance of Australian schooling, given its obligation to implement treaties to which it is a signatory.