Disclosed is an attachment (500, 600) for a fence post (510, 610). The attachment comprises a mounting portion (516, 602) that is configured for being secured at an in-use upper end of the post. The attachment also comprises at least one elongate extension arm (518, 520, 604) that is integrally formed with and extends from the mounting portion to a free distal end. The extension arm has a curvature for at least part of a length thereof such that, in use, the at least one elongate extension arm (518, 520, 604) is able to extend over and interact with an uppermost edge of the fence post (510, 610), with the free distal arm end being located laterally away from the post (510, 610) and lower than the uppermost edge of the fence post. The attachment (500, 600) can support an auxiliary fence (750) with respect to each fence post (510, 610). In this way, the attachment (500, 600) can assist in the transfer of forces from the at least one elongate extension arm (518, 520, 604) into the fence post (510, 610) where the force can best be accommodated.
