The book content corresponds to a course of the International Summer School of Theoretical Geodesy held every 4 years under the sponsorship of the International Association of Geodesy. This particular course, that was given at the International Centre for Theoretical Physics in Trieste, has been dedicated to the theory of satellite altimetry as a response to the increasing need of scientific work in this field due to important recent and forthcoming space mission. The course was conceived to supply a good theoretical basis in both disciplines, i.e. geodesy and oceanography, which are deeply involved in the analysis and in the use of the altimetric signal. The main items of interest are the physical theory of ocean circulation, the theory of tides and the ocean time-variability, from the point of view of oceanography and the orbit theory, with particular regard to the formation of the radial orbital error, the so-called cross over adjustment, the analysis of geodetic boundary value problems, the integrated determination of the gravity field and of the radial orbital error, from the point of view of geodesy. All these arguments are treated from the foundation by very-well experts of the various fields, to introduce the reader into the more difficult subjects on which advanced research is currently performed. The peculiarity of the book is in its interdisciplinarity as it can serve to both communities of oceanographers and geodesists to get acquainted with advanced aspects one of the other.