N.J. Stat. § 40:33-13.7
The regional library shall be under the management and control of a board of trustees to be designated as "the trustees of the (names of the participating counties) regional library" or by other appropriate designation. The board of trustees shall consist of 1, 2 or 3 members from each of the participating counties, as provided in the agreement. The trustees shall be appointed by the respective boards of chosen freeholders for 5-year terms ending on December 31. Vacancies shall be filled for the unexpired term only. No trustee shall be appointed to more than 2 consecutive 5-year terms. Trustees shall serve without compensation.
The initial terms of the trustees shall be so fixed in the joint library agreement to insure that no 2 terms of the trustees appointed from any one county shall expire in the same year, and, as nearly as may be, that the least possible number of terms of all the trustees shall expire in the same year.
N.J.S. § 40:33-13.7