N.J. Stat. § 18A:17-14.1
A board or the boards of two or more districts may, under rules and regulations prescribed by the State board, appoint a school business administrator by a majority vote of all the members of the board, define his duties, which may include serving as secretary of one of the boards, and fix his salary, whenever the necessity for such appointment shall have been agreed to by the county superintendent of schools or the county superintendents of schools of the counties in which the districts are situate and approved by the commissioner and the State board.
Nothing in P.L. 1996, c. 111(C.18A:17-24.1 et al.) shall prohibit a school district from subcontracting its school business administrator to another school district pursuant to the provisions of P.L. 1973, c.208 (C.40:8A-1 et al.), in which case credit toward tenure acquisition shall accrue only in the primary district of employment.
N.J.S. § 18A:17-14.1