This volume contains all of the fifteen invited review papers presented at the International Symposium on the Physics of the Magnetosphere, held in the U. S. Department of State, Washington, D. C., September 3–13, 1968. The contributed papers presented at the Symposium are not included; they are appearing in other appropriate journals. By arrangement with the Inter‐Union Commission on Solar‐Terrestrial Physics (IUCSTP), the Symposium was sponsored by the Committee on Space Research (COSPAR), the International Association of Geomagnetism and Aeronomy of the International Union of Geodesy and Geophysics (IUGG‐IAGA), the International Scientific Radio Union (URSI), the International Union of Pure and Applied Physics (IUPAP), and the International Astronomical Union (IAU). It was held by the U. S. National Academy of Sciences and the NASA Goddard Space Flight Center. The Symposium was attended by 325 scientists representing 18 different co