Abstract: Corner forming apparatus is disclosed, including novel generally L-shaped member having a seating flange projecting from one leg of the member substantially parallel to the other leg. The seating flange is adapted to shield an edge of a panel when the panel is seated on the seating flange. The other leg of the L-shaped member is securable to a panel-support beam mounted on the back of said panel, and is provided with at least one aperture therein to receive fastening elements for securing another panel to the other leg such that a surface of the other panel and the outer surface of said one leg are substantially coplanar.Also a unique outside corner waler useful with the inside corner forming member in quick and accurate assembly of a complete corner wall form. Said waler having a major leg and a minor leg each joined at one end at right angles by an apertured web and being of respectively different heights such that said waler seats at about a 45.degree. angle.