Surfactants responsive to pH, temperature, CO2, and light are known, however, our recent work has shown, for the first time surfactants that are magneto-responsive, and also ionic liquids. These represent a new class of compounds termed magnetic ionic liquid surfactants (MILSs). These MILSs are of great interest as they exhibit both amphiphilic behaviour and are magnetically active. Hence, they have novel potential applications allowing non-invasive recovery of ILs from reaction mixtures (see Figure 3), facile separations and targeted delivery. In order to understand how these compounds function it is important to investigate specific cation-anion effects. Interrogating air-water monolayers by neutron reflectivity (NR) is the best way to gain unambiguous information on interfacial association in the presence and absence of an applied magnetic field.