Structural designs for composite laminated systems can be optimized for a fail-safe in-service performance by introducing the built-in cumulative-damageindicators for the progressive degradation of material properties. This design methodology is based on the concepts of the characteristic failure signature (CFS), the cumulative-damage-states and a load drop sequence that characterize the progressive accumulation of damage. The cumulative damage mechanics is based on the 3D laminate analysis that is used to predict a nonlinear stress/strain response, accumulation of damage and failure behavior. The nonlinear analysis involves an incremental formulation that couples the 3D laminate analysis with a progressive ply-failure methodology. The failure signatures are shown to have unique “safety features” that depend on the ply stacking sequence and predominant loading. A quantitative description of the failure process is provided by the corresponding load-drop sequence. Various examples of failure envelopes, characteristic failure signatures, a new safety criterion and the “safe CFSs” that lead to the desired controlled failures are discussed for anisotropic laminates. The safety criterion may serve as a basis for the structural safety requirements.