Abstract: An animal barrier for use in a vehicle is formed by a frame having an opening therein, and partition members mounted to the frame. First and second partition members are spaced apart to define the opening therebetween and are moveable relative to the frame so as to vary the width of the barrier and the width of the opening. A third partition member is slidably mounted to the frame so as to be moveable between a closed position in which it overlies the opening so as to substantially close the opening, and an open position in which is removed from the opening. In the open position, the third partition member may be located to one side of the opening, overlapping one of the first and second partition members or may be located above or below the opening, away from the first and second partition members.