A technique we have recently developed enables us to simply produce stable, homogenous and thin oil layers, using polymer surfactants, in a simple manner on water. These are suitable for neutron reflectometry directly at the oil-water interface. Deuterated mixed oil-soluble and water-soluble polymer-derived surfactants (respectively, polyisobutylene-derived, PIBSA, and polyacrlyamide-derived, PAM) will be studied at the air/water and oil/water interfaces. Combinations of PIBSA with PAMs of varying amphipathy will be studied as a function of applied surface pressure to examine their mixing, lateral segregation, aggregation and preferential dissolution into either the oil or the water phase. These measurements will complement X-ray reflectivity and SANS measurements on emulsions.