N.J. Stat. § 18A:17-15
The board of education of a Type I district and of any Type II district, now having or hereafter authorized to have a superintendent of schools, may, by contract appoint, for a term of not less than three nor more than five years and expiring July 1, a superintendent of schools by the recorded roll call majority vote of the full membership of the board.
A superintendent of schools may be appointed for a like term also in any other Type II district or in any other two or more Type II districts as follows:
Application for the establishment of the office of superintendent of schools for a district or for two or more districts which determine to share a superintendent shall be made to the county superintendent of the county or the county superintendent of each of the counties in which such district or districts are situate and if said application is agreed to in writing by such county superintendent or county superintendents and shall be approved by the commissioner and the State board, the board of education of such a district so applying may appoint a superintendent of schools for a single district in the manner hereinbefore provided or may appoint a superintendent for two or more districts in the manner provided by section 4 of P.L. 1996, c. 111(C.18A:17-24.1).
N.J.S. § 18A:17-15