A cable tie includes an elongate generally planar strap (14) and a cable tie head (12). The head of the cable tie includes an aperture (22) therethrough for insertably accommodating the strap. A locking device is supported by the head and extends into the aperture. The locking device permits movement of the strap in an insertion direction and prevents substantial movement of the strap in a withdrawal direction. The locking device includes a hingedly mounted support member (26) extending into the aperture and a barb (24) supported adjacent the support member. The barb and the support member are movable into locking engagement with the strap to prevent withdrawal of the strap from the head aperture.