Polymers adsorbed or otherwise attached to interfaces provide an extremely powerful tool to control the forces that act between interfaces. The functionality of these attached polymer layers depends on how they react when compressed between two surfaces coming into very close proximity. We have recently developed a surface force style apparatus that allows direct measurements of the structure of polymer layers under compression using neutron reflection. We propose to use this apparatus to investigate the compression of a thin (~100nm) poly(vinyl pyrrolidone gel layers) in water. This will provide the unique opportunity to relate the structure of this gel layer under compression to the applied force. It will also allow us to test for the first time an important recent improvement to the setup: an optical technique that separately measures the inter-surface distance.