The administrative structure of the Society is made up of the Executive Committee and the Council. The Executive Committee and the Council are responsible for the management of the affairs of the Society in accordance with the policies and guidelines of the Society. They are accountable to the General Membership consisting of all voting members of the Society. The terms of office of the Executive Committee and the Council begin on the last day of the ISI Biennial Session and end on the last day of the following ISI Biennial Session. Wherever it is not explicitly stated below, the approval of the Executive or the Council means a decision by simple majority.