During the late 1980s, the high school went from being a parish high school to a diocesan high school, separating completely from the now-defunct St. Mary Elementary School (K-8). As a result of the change the high school went through several name changes, including St. Mary Regional High School (1988–2000), St. Mary Diocesan High School (2000–2001). On June 11, 2001, then Diocese of Metuchen Bishop Vincent Breen announced that Saint Mary's would close and reopen under a new name the following fall. In September 2001, the school was named Cardinal McCarrick High School, in honor of Theodore Edgar McCarrick, the first bishop of the Diocese of Metuchen.