Apparatus for generating, applying and maintaining compression to a site in a human or animal body, the apparatus comprising: a staple comprising: a bridge configured to be elastically bendable; a first leg connected to the bridge by a first hinge region configured to be elastically bendable; and a second leg connected to the bridge by a second hinge region configured to be elastically bendable; wherein the first hinge region comprises a first hole configured to mate with a first element of a delivery device and the second hinge region comprises a second hole configured to mate with a second element of a delivery device; and wherein the first and second legs are angled toward one another when they are in an unstrained state; whereby, when the staple is mounted to a delivery device so that the first hole of the first hinge region mates with a first element of a delivery device and the second hole of the second hinge region mates with a second element of a delivery device, and when the delivery device applies a force to the bridge of the staple so as to reconfigure the bridge of the staple, the first and second legs are pivoted away from one another toward a parallel disposition.