Abstract: Wall elements have edge cavities that extend inwardly through their side edge and have locking lugs inwardly of the cavities. Lock pins are provided between the wall elements for each cavity and are associated with the locking lugs for securely locking two wall elements together by moving the wall elements into edge-to-edge abutting relation. The cavities have a leveraging surface capable of pivoting the lock pins out of engagement with the locking lugs and thus disconnection of the wall elements upon relative vertical movement of adjacent wall elements. The invention is capable of assembling knock-down walled enclosures such as work spaces of substantially any size and shape.