This volume contains the proceedings of the Fourth Taniguchi International Symposium on the Theory of Condensed Matter, which was held at Senkari Semi nar House of Kwansei Gakuin Universi~y in Sanda-shi, Japan, during the period of 3-8 November 1981. The topic of the symposium was "Anderson rocalization," one of the most fundamental problems in condensed-matter physics. Since Anderson's classic paper was published in 1958, much theoretical and experimental effort has been performed to study the problem of electron localization in a random potential. Quite recently, Abrahams, Anderson, Licciardello, and Ramakrishnan proposed a scaling theory of the Anderson lo calization which made it possible to perform microscopic investigations. Rapid progress has followed and we are now getting a coherent picture of the behavior of electrons in disordered systems. When we organized the symposium, we asked Dr. Anderson to participate in it and to give a review talk on theoretical aspects of the problem. Though he kindly accepted our invitation, he could not come due to a sudden illness. A review talk was given by Professor Thouless who kindly accepted our request to take the place of Dr. Anderson. Fortunately, Dr. Anderson has since re covered from his illness.

Inhalt
I. Anderson Localization.- Survey of Localization: Are Noninteracting Electrons Fully Understood?.- The Anderson Transition and the Nonlinear ?-Model.- Anderson Localization in Nonlinear ? Model Representation.- Self-Consistent Diagrammatic Theory of Anderson Localization.- Self-Consistent Treatment of Two-Dimensional Anderson Localization in the Absence of Time Reversal Symmetry.- Localization in One-Dimensional and Quasi-One-Dimensional System.- Numerical Studies of Localization in Two Dimensions.- Numerical Study of DC Conductivity in Two-Dimensional Disordered Systems.- Interaction Effects in Disordered Systems.- Interaction Effects in Two-Dimensional Disordered Systems.- Localization Versus Superconductivity.- Kondo Effects and Localization in Two Dimensions.- Application of the Recent Theory of Anderson Localization to Doped Semiconductors.- Dielectric and Optical Anomalies Near the Anderson Metal-Insulator Transition.- Localization in n-InSb.- Interplay of Disorder and Coulomb Interactions in Anderson-Localized States.- Extended Effective Medium Theory for Conductivity.- II. Quantized Hall Effect.- Hall Effect and Electron Localization in a Two-Dimensional System in Strong Magnetic Fields.- Localization in a Strong Magnetic Field.- The Quantized Hall Effect and Other Macroscopic Quantum Phenomena.- A Calculation of Two-Dimensional Hall Conductivity Under Strong Magnetic Fields Wigner Representation.- III. Spin Class.- Breaking of Ergodicity in Disordered Systems: The Case of Spin Glasses.- Index of Contributors.