Interfacial tensiometry (IFT) is used to measure the interfacial tension between two phases; the IFT works by measuring the curvature of a droplet of one phase immersed in another phase. This curvature can be regressed back to an interfacial tension. These phases can be liquid-liquid or gas-liquid. At the Fluid Science & Resources group the IFT is used to study the effect surfactants have on the oil-water interfacial tension and how well different surfactants pack along the interface.