Abstract: Concrete form systems and hardware components thereof wherein the inner and outer walls are composed of abutting, side-by-side plywood sheets and are tied together by wall ties and stud-bearing plates, wherein the improvements reside in: metal straps serving as inside and outside corner braces with right angled legs having specially spaced, transverse, tie-rod-receiving slots in one longitudinal edge of each leg; rectangular plates having a center hole and two studs projecting from its inner face on opposite sides of the hole, said plate having longitudinal, flange edges or lips forming the sides of a trough in the outer face; flat, metal straps for securing filler strips between plywood panels, which straps have specially spaced, transverse, tie-rod-receiving slots in one longitudinal edge; and hingedly connected, rectangular panels forming a right angle corner for the outside wall, said panels being foldable to a shipping and storing position in which the panels are in overlying, substantial face-to-face pa