Abstract: An anchor-clamp is disclosed for clamping to a prestressing member (50) intermediate its length and over a support (68). The clamp (FIG. 1), after initial assembly, is packed in polystyrene blocks (62, 64) for shipment. At the site of use, the anchor-clamp, still in its foam package, is assembled to the prestressing member (50) and then the concrete is poured and allowed to set. After hardening of the concrete, the prestressed member (50) is stressed in the conventional way, the polystyrene package is removed from about the anchor-clamp and the clamp is operated to clamp the stressed prestressing member (50). Thereafter, the entire clamp is imbedded in concrete. When only one intermediate anchor-clamp is used, it may be clamped to the prestressing member (50) prior to the stressing of the same.