Since the start of the space age more than 50 years ago, various space technology applications - including communication, navigation, and remote sensing - have advanced significantly. To meet the challenges in each application category, special orbits such as geo-stationary, semi-synchronous, Molniya, sun-synchronous, and frozen have been invented or selected. Although a good number of texts on the principles and applications of astrodynamics have been published, a book is needed to summarize the perturbation theories and control, or station keeping, algorithms for understanding the dynamics, stability, and maintenance of those orbits. "Applied Orbit Perturbations and Maintenance" was written to meet that need. It summarizes, in appropriate technical and mathematical detail, perturbation theories and station keeping algorithms for various types of mission orbits and constellations. Space mission designers/analysts and systems engineers will put this book to great use.