Recent results from the large-scale experimental evaluation of a multi-story coupled shear wall system with fully post-tensioned coupling beams are discussed. In this novel system, high-strength unbonded post-tensioning (PT) strands are used to couple (i.e., link) reinforced concrete wall piers. To validate the new system, reversed-cyclic quasi-static testing of a 40%-scale coupled wall structure with the proposed details was conducted. The laboratory specimen represented the most critical bottom three stories of an eight-story prototype structure, consisting of two C-shaped wall piers, six coupling beams (two beams at each floor level), tributary slabs at each floor, and the foundation. The other (less critical) regions of the structure were simulated analytically. The test specimen performed well, demonstrating ductile behavior through the completion of three full cycles at a lateral drift greater than the 3.0% roof drift demand used in design, thus supporting the design approach, assumptions, approximations, and tools. Ultimately, the test results also support the ACI classification of these structures as "special" reinforced concrete shear walls in moderate and high seismic regions of the U.S.