A correlation between the chemical composition of petroleum and the surface activity of oil-alkaline water interface is made. The polar components in oil are responsible for the ultralow interfacial tension. The active acids consist of a variety of nonhomogeneous species, some of which are chemically bonded. Mineral acid treatment of crude oil and sequential activation using incremental alkaline concentration in the flood were proposed to make maximum utilization of active species in crudes. Sandpack core flooding results are presented.