A coordinated research program involving synthesis, characterization, and rheology has been undertaken to develop advanced polymer systems which should be significantly more efficient than polymers presently used for mobility control and conformance. Unlike the relatively inefficient, traditional EOR polymers, these advanced polymer systems possess microstructural features responsive to temperature, electrolyte concentration, and shear conditions. Desired rheological behavior is accomplished by carefully controlling hydrophobic or ampholytic interactions between individual polymer chains. The polymers proposed circumvent major problems inherent in even the best conventional EOR polymers in which molecular weight is usually compromised in order to allow sufficient viscosity and uniform permeation without plugging the porous network. Additionally, conventional polymers are often poor mobility control agents in the presence of calcium, barium and sodium salts, precluding use in offshore recovery. By contrast, these advanced polymers would maintain high viscosities or behave as gels under low shear conditions and at elevated electrolyte concentrations expected in some reservoirs. At high fluid shear as, intermolecular aggregates would dissociate yielding low viscosity solutions, subsequently reducing potential problems of face-plugging and shear degradation during injection. Also, certain copolymer compositions have been developed which emulsify hydrocarbons and viscosity the making fluid. Initial laboratory experiments have demonstrated the promise of such systems in higher salt, higher temperature reservoirs or as potential surface/viscosijers to mobilize entrapped oil.