AbstractFloor slabs can be utilized effectively to increase the strength and stiffness of a frame by providing continuous slab reinforcement across column lines. This review discusses the influence of floor slabs on the behavior of connections in typical steel buildings, with emphasis on American construction practices. The emphasis is on simplicity of detailing so that the force transfer mechanisms can be understood. The discussion aims to demonstrate three important concepts. First, the detailing of both the slab steel and the steel connection can have a great influence on frame performance, by turning ‘pinned’ connections into partially restrained or semicontinuous ones. Second, ignoring the effect of the slab, as is the conventional practice today, is not always a conservative approach. This is particularly important when seismic or other large accidental overloads occur, as the ductility and toughness of the structure can be impaired by unexpected failure mechanisms tied to slab effects Third, judicious use of composite action in the connections can lead to very economical and structurally efficient solutions. An extensive set of references, both to detailed design guidelines and general background issues, is provided.