The principal challenge of upscaling techniques for multi-phase fluid dynamics in porous media is to determine which properties on the micro-scale can be used to predict macroscopic flow and spatial distribution of phases at core- and field-scales. The most notable outcome of recent theories is the identification of interfacial areas per volume for multiple phases as a fundamental parameter that determines much of the multi-phase properties of the porous medium. A formal program of experimental research was begun to directly test upscaling theories in fluid flow through porous media by comparing measurements of relative permeability and capillary-saturation with measurements of interfacial area per volume. During this reporting period, we achieved the milestone of using Optical Coherence Imaging (OCI) to image to the back of the first layer of grains in a sandstone sample. This is the first time that OCI has been used to image through sandstone. Information on grain geometry was obtained as deep as 400 microns into the sample. This report also describes the work performed to achieve the milestone on the measurement of interfacial area per volume, capillary pressure and saturation in two dimensional micromodels structures that are statistically similar to real porous media. This report contains the first quantitative experimental measurements of interfacial area per volume in any system.