The function of trustees is discussed, based on in-depth interviews with trustees and presidents of 10 private liberal arts colleges. After a brief overview of the trustee mandate and role and of recent attempts to redefine that role, major models of campus governance are summarized. In considering how boards diminish the presidency, attention is directed to the president as a political officer and bureaucrat, and the effect of the board's committee system. The board's evaluation of the president and sources of information about the president are also addressed. To demonstrate how difficulties between a board and president may arise and be resolved, case histories are presented of how two boards evaluated presidents. The board is also described as a discrete subunit of the collegiate organization, with a focus on the status of its members as volunteers and their reasons for serving. The role of the board chairperson, the board's financial activities, and recruitment and retention of board members are also covered. Additional topics include: three models of board behavior, the gap between policy and administration, the impact of the board on the college, and implications for theory and practice. Appendices provide information on the study methodology as well as sketches of the trustees, presidents, and 10 colleges (anonymous) that were studied. (SW)