Off-specular neutron reflection beamtime is requested to study phase separation at the air/water interface. Stability of systems, such as polymers, is a major area of interest as many technological applications, for example biological scaffolding and templating, require highly stabilized systems. Before complex ¿real life¿ systems can be studied using this technique, experiments on model and well controlled systems must first be performed. Here, the natural incompatibility of fluorocarbon and hydrocarbon moities will be exploited to drive a controlled local phase segregation at the air/water interface. The natural neutron contrast between the fluorinated and hydrogenated components will be exploited to give a full picture of the system under study.