Abstract: The invention provides a new fence system permitting the construction of privacy fences; perimeter fences; boundary fences and rail fences using a small number of different fence elements. These elements consist of a hollow elongated post/rail element of semi-octagonal transverse cross-section; an end cap for the element when used as a post; an L-shaped connecting bracket; a panel element and an end cap therefor; a clip for fastening panel elements to the rails; closure elements for the rails and posts that also locate and hold the panels when they are engaged in slots therein. The panels are provided near to their center with a plurality of spaced stiffening walls to resist buckling under heavy loads.