The effectiveness and legitimacy of the Council of Europe can be undermined by the actions of Member States which fail to comply with their international law obligations of genuine cooperation with the organization. This article first briefly examines the practice of international organizations in applying sanctions such as expulsion and suspension to their members. It then explains why it is necessary to discuss potential sanctions that the Council can apply in the context of current controversies involving the Council and Member States. It will be argued that the scale and intensity of challenges distinguish the current state of affairs from other ‘problematic’ periods in the Council's history. It proceeds to outline the considerations that should be taken into account in deciding whether a Member State should be suspended or expelled. These considerations include the implications of sanctions on the legitimacy of the Council of Europe, the level of human rights protection and the financial stability of the organization.