This paper presents an overview of the research performed by the Orbital Mechanics Section of Delft University of Technology on the precise orbit computation of Seasat and the processing of the satellite's altimeter measurements. After a general description of the Seasat tracking and orbit characteristics, the applications of the altimeter data for geophysical and oceanographic investigations and as tracking data are addressed. Subsequently, the accuracy of orbit determination achieved by processing laser range data only or laser ranges in combination with altimeter height cross-over differences is discussed, and the identification of the radial orbit error from altimeter height residual profiles is described. The geographical correlation of the radial orbit error is analysed and the development of a tailored gravity model is addressed. Finally, the elimination of the residual radial orbit error is discussed and an example is given of the computation of a mean sea surface.