Many key problems in industrial and biological processes involve mechanisms which occur at solid-fluid interfaces. Adsorption, lubrication, dispersion stability, sol-gel fabrication, and membrane transport all involve solid/fluid interactions. The goals of this research are to understand and predict, at the molecular level, the behavior of fluid next to or between solid surfaces. Theoretical aspects will focus on development of molecular theories for strongly homogeneous fluids. Experimental research will focus on use of the surface force apparatus and will complement the theoretical work.