This report presents the results of a program to develop a theoretical analysis of the effects of frame response on basement shelters in tall shelters. The objective was to determine the effect on an upgraded basement key worker shelter of the aboveground portion of the structure being subjected to a blast wave that would destroy the building. Both steel and reinforced concrete frame structures were investigated, with most emphasis on poured-in-place reinforced concrete beam, slab, and girder type framing and poured-in-place flat-slab and flat-plate construction. A prediction technique using both hand and computer analysis was developed and tested using a previously demolished 15-story cast-in-place reinforced structure. The analysis indicated that the upgraded basement would have survived even though the above ground-portion of the structure was exposed to 50 psi.