The right of a land- owner to assurance that his/her neighbor’s land will provide support against any slippage, cave-in or landslide. should the adjoining owner excavate into the soil for any reason (foundation, basement, leveling) then there must be a retaining wall constructed (or other protective engineering) to prevent a collapse. a classic example: a developer excavated into a hill along both the western and southern lines to create a pad for an apartment building and delayed putting in the retaining wall. cracks appeared in the buildings next to the digging site, and the owners filed a lawsuit asking for an injunction to require the developer to build a wall. the judge so ordered, but the cave-in occurred anyway, the neighboring buildings toppled into the hole, and, in the subsequent lawsuit by the owners of the neighboring fallen buildings, the developer had to pay the entire value of the buildings which were destroyed. most lateral support problems are less dramatic.