According to the bylaws (Article II. Section 7), the Board of Trustees “is responsible for the management and conduct of the affairs of the corporation.”
The Board of Trustees consists of twelve members: the five members of the Executive Committee, the Chair of the Editorial Council and six members who are elected directly by the membership of the society. These elected members serve for three years so that the terms of two members expire every year. Elections of two new members (from four candidates) take place every year, with nominations coming from the current Board of Trustees. Members elected directly by the membership cannot serve for two consecutive terms.
The five members of the Executive Committee and the Chair of the Editorial Council also belong to the Board of Trustees.
See a list of past members of the Board of Trustees here.