Perform3D is a structural-engineering software useful for the performance assessment of structural systems. State-of-the-art constitutive-modeling capabilities enable characterization of material nonlinearity, including strength and stiffness degradation during component-level hysteresis. Analysis capabilities also extend to geometric nonlinearity and effects associated with P-Delta behavior. Advanced modeling tools enable a sophisticated simulation of structural behavior. Components may be grouped according to type, location, and limit state before evaluation proceeds in terms of strength or deformation-based demand-capacity ratio. The dynamic display of D-C usage is available through color-coordinated time-history animations.