This monograph explores the topic of Fatty Acid Binding Proteins with special emphasis on the basis of binding specificity of these receptor proteins for hydrophobic compounds such as Fatty Acids. The text provides in-depth details about the structure determination of a particular Fatty Acid Binding Protein found in the muscle cells of Locusta migratoria. The rest of the text deals with the isolation of another Fatty Acid Binding Protein found in the kidneys of male rats and the transport properties of Sulfonylureas , a class of hydrophobic compounds used to treat type II Diabetes mellitus.