With the Constitution of 1867, Canada inherited a system similar to that of the British Parliament, in which the formal powers of the British government are divided between the Ottawa government and the Provinces. This division of powers, which has remained substantially unaltered, is now undergoing numerous variations due to the competition among the various levels of government to conquer new areas of competence. After describing the division of constitutional powers in Canada, the author reports on the debate on limitations to this power and on the ways in which their division can be improved or adjusted. The author reconstructs the various types of informal power of amendment normally utilized. He emphasises in particular that the exercise of spending power allows, through the leasing of competencies or their negotiation, the delegation of various powers.