In this paper we are concerned with adsorption, structure, morphology, and dynamic properties of food dairy proteins (beta-casein, caseinate, and whey protein isolate (WPI)) and water-insoluble lipids (monopalmitin and monoolein) at the air-water and oil-water interfaces. Combined surface chemistry (surface film balance and dynamic tensiometry) and microscopy (Brewster angle microscopy (BAM)) techniques have been used to determine the adsorption, structure, morphology, relative film thickness, relaxation phenomena, and dilatational rheological characteristics of emulsifiers (proteins and lipids) at fluid-fluid interfaces, including the effect of temperature. The derived information shows that protein and lipid type and temperature affect the interfacial characteristics. The nature of emulsifier (protein or lipid) interactions at the interface has an important role in their physicochemical characteristics. Important functional differences have been established between proteins and lipids, and between globular (WPI) and disordered (beta-casein and caseinate) proteins.