The aim is to use Neutron Reflectivity (NR) to gain essential information on the adsorption properties of fluorocarbon (FC)/ hydrocarbon (HC) mixtures in commercial fire-fighting foam formulations. These practical mixed surfactant systems (Surfactants shown in Figure 1) have already been studied in air contrast matched water (ACMW), and initial analysis has been carried out. However, further analysis, including different solvent contrasts are required to fully characterise the mixed system data to provide essential information on which surfactants are dominating the interfacial properties of the fire-fighting foam formulation. This is the final stage in a new 3-year program, including NR, so that F-carbon surfactants can be replaced by more environmentally-responsive low-F or hydrocarbon analogues. A paper is currently in preparation for results related to this work.