A terminal post for a barrier includes an upright portion having an aperture positioned, so that in use: the aperture is located in a region of the upright portion above a ground engaging portion of the upright portion; and wherein located on one side of the aperture is a transverse reinforcing member which includes a slot for receiving a cable. At least one groove, or pair of notches is provided located beneath the aperture, and form(s) a predetermined fail line, along which the post will deform, upon receiving a substantially inline impact, which causes the transverse member to move to release the cable, and wherein the aperture is dimensioned to allow the terminal end of the cable formally retained by the slot to pass therethrough.