This book covers the entire field of geodesy and is intended to serve as an introductory textbook for graduate students as well as a reference for scientists and engineers in the fields of geodesy, geophysics, surveying engineering, and geomatics. It provides a systematic overview of fundamental theory in physical geodesy, reference systems, and space and terrestrial measurement methods, together with the respective modeling techniques.<BR><BR>The fourth edition has been thoroughly revised and extended in order to reflect the central role which geodesy has achieved in the past ten years, within the concert of geosciences observing the global change of our planet. Space techniques are now the predominate tool for measuring the geometric shape of the earth, its gravity field, and its rotation. The establishment of reference systems and standards has followed these developments, with far-reaching consequences for applied geodesy and geo-information science. Increasing emphasis is given onto the determination and interpretation of temporal variations of the Earth's system, thus contributing to geodynamics research.<BR><BR>The text is well illustrated by sketches of principle and by selected examples of instruments, networks and models, including recent results of dedicated space missions. An extensive reference list supports further studies.