A robust structural system can withstand extreme loads and localized damage, such as the failure of a column, without widespread (or disproportionate) collapse. This research opportunity focuses on investigating and enhancing the robustness of structural systems commonly used in building construction in the United States. Opportunities exist for (1) experimental investigation of new steel and reinforced concrete connections with enhanced robustness against column loss; (2) development of experimentally-validated reduced-order computational modeling approaches that enable analysis of complete structural systems; and (3) extension of experimental results to the low- and high-cycle fatigue loading regimes relevant to earthquakes and synoptic windstorms, respectively.