Steel-Concrete-Steel (SCS) composite construction consists of two relatively thin steel plates with the space between filled with concrete. Various forms of this construction exist, using overlapping shear studs and single bar connectors to provide shear reinforcement to the concrete and provide a shear transfer at the interface. The problem with current systems that rely purely upon shear studs or bar connectors is that they are prone to slip between the steel faceplates and concrete core. This slip leads to a loss of composite action causing a loss of stiffness and a reduced fatigue life. An extensive experimental programme consisting of 32 beam specimens and 34 other small scale specimens formed the basis for the study of the behaviour of surfaced SCS specimens under a variety of load conditions. The results of this test program showed that surfaced SCS specimens behaved in a more composite manner. This increase in composite action manifested itself in a number of ways. • Reduced slip between steel plate and concrete core • Increased stiffness of specimen • More even crack distribution This extensive experimental study was backed up with an analytical study to understand and predict the behaviour of the surfaced SCS elements. This study has led to a new method of predicting the capacity of such sections, to a greater degree of accuracy than current methods allow. Further to this a FE parametric study was carried out to investigate the sensitivity of the elements to changes in the main geometrical and material variables.