Novel technologies are needed to address the urgent healthcare requirements of patients in the developing world and other resource-limited settings. Diagnostic devices that provide critical patient information at the point of need play a key role in the treatment and monitoring of disease. Such devices must be robust, simple to use, actionable, and extremely low in cost. Paper and other porous media provide an attractive platform from which to build devices that are able to address these needs. In an effort to expand the capabilities of porous media in diagnostics, we present a novel platform based on patterned paper microfluidic devices. In particular, 3-dimensional devices formed by stacking multiple layers of patterned paper provide the ability to perform many fluidic handling operations including: filtration; splitting; mixing; incubation; capture; and separations. Diagnostics For All (DFA) is developing tests based on this platform, in order to provide highly-functional diagnostic devices at unprecedented low cost. In this presentation, we will describe some specific examples of paper-based tests designed specifically for use in resource-poor areas.