Four slab-column subassemblages, modeled after a typical reinforced flat plate building, are tested under combined gravity and lateral loads. The testing program incorporates two levels of gravity loads and compares the effects of biaxial versus uniaxial lateral loading on connection behavior. To study the effectiveness of connection repair, one of the tested specimens is repaired with epoxy/grout and reloaded. The post failure behavior of slab-column connections is investigated and the adequacy of slab reinforcement detailing in preventing progressive collapse is assessed. Existing strength and lateral stiffness models are compared with experimental results. Data from past research are collected to investigate the ductility and drift capacity of slab-column connections. The seismic design of reinforced concrete flat slab buildings is discussed.