5. Current codes require special transverse reinforcement over the full height of vertical boundary elements for structural walls. Tests of isolation cantilever walls indicate that this reinforcement is only needed within hinging regions of walls. Significant savings in reinforcement are possible because hinging regions do not propagate over the entire wall height. Cantilever tests indicate that the primary zone of damage extends over a height approximately equal to the horizontal length of the wall. Test specimens had constant section properties and therefore, hinged at the base. In an actual structure, potential hinging and damage is most critical at the wall base. However, hinging regions at discontinuities resulting from strength taper, changes in geometry, or higher mode inertial forces must also be considered.