Private-independent school Board Presidents often ask, “What is the right size Board for a school with our enrollment and grade configuration?” For those Board Presidents seeking to implement ISM’s “strategic Board” concepts and practices, our standard answers include the following. There is little relationship between school enrollment and school grade-configuration, on the one hand, and the number of Trustees needed to do the work of the Board, on the other. Board structure and function are factors almost entirely independent of school size and student age-range. That said, ISM’s second-level answer to the question is this: The work of the Board normally requires about 15 to 20 people annually immersed in “doing governance.”