Abstract: Building structures are complex systems consisting of different structural members. It is of great significance to the seismic design of structures to control the dynamic response and failure process under strong earthquakes at the system level. To ensure that the building structures show "stable, orderly, gradual, and controllable" seismic failure mechanisms and modes, one effective way is to pre-design a clear damage mechanism and improve the overall post-yield stiffness of the structure. To this end, the "system capacity design method" was proposed and developed. The method sets the primary and secondary structures at the system level so that the inelastic dynamic response of the structure is controlled by the primary structure with higher seismic capacity, thereby realizing the control of the seismic performance. This paper summarizes recent important research progress of key scientific issues in the system capacity design method, and discusses its engineering significance and future development.