A ten-year study by the Precast Seismic Structural Systems (PRESSS) Research Program produced three approaches to seismic design using precast concrete: Hybrid Post-Tensioned Precast Frame: Precast concrete beams are connected to multi-story columns by unbonded, post-tensioned strands that run through a duct in the center of the beam and the columns. Mild steel reinforcement is placed in ducts on the beam, which are sleeved through the column and grouted. The reinforcement yields alternately in tension and compression and provides energy dissipation, while the post-tensioned strands act as “rubber bands” that support the structure after the seismic event ends. There are no column corbels with the vertical shear resistance provided by the post-tensioning strand. The post-tensioning steel balances the mild steel reinforcement, recentering the frame after flexing. Pretensioned Precast Frame: This incorporates multi-span beams cast with a partially de-bonded pre-tensioning strand set on the columns. The columns’ reinforcing steel extends through the sleeves inside the beams. Reinforcing bar splices ensure continuity above the beam. As the frame displaces laterally, the de-bonded strand remains elastic. While the system dissipates relatively less energy than other systems, it recenters the structure after a significant seismic event. Although the frame performs satisfactorily in tests, it can’t act as the sole seismic-force-resisting system in regions of high seismic risk. Pretensioned Precast Frame (PRESSS Shear-Wall Design): This method uses an innovative approach for anchoring and connecting jointed walls to lengthen the structural period and reduce the design-based shear forces. Gravity loads are mobilized to partially resist overturning from the lateral ground motions. The system also considers the behavior of the jointed shear-wall system when the wall lifts and rocks, along with its effect of design forces. Unbonded post-tensioning forces recenter the wall system when the load is removed with minimal residual drift after a design-level earthquake. Recentering is ensured by relating the elastic capacity of the post-tensioning system to the yield strength of the panel-to-panel connection. The shear wall is expected to displace laterally to approximately 2% of story drift under a design-level earthquake.