Abstract: Apparatus for vertically adjusting forms used for constructing concrete walls poured in several horizontal segments comprises a jack and means for supporting the jack from a pair of adjacent she-bolts previously installed near the top of a previously poured wall segment. The supporting means includes a pair of hangers adapted for hanging from the she-bolts and a support member connected between lower portions of the hangers. For horizontal adjustment the jack is preferably mounted on a plate which is slidable along the support member and which may be clampable thereto. Lower portions of the concrete forms are modified by installation of headers and bearing plates to receive the jacking forces. In the preferred embodiment the jack supporting member is about as long as the spacing between adjacent she-bolts, or about two feet long. In a first variation the support member is constructed to be shorter, the hangers being inclined rather than vertical, and the jack being fixed to the support member.