Abstract :
This Special Issue is dedicated to Thomas A. Fischetti on the occasion of his retirement as Head of the NASA Geodynamics Program. It was his leadership which enabled the formation of the Crustal Dynamics Project which is now the NASA focus for a global program for measuring the movement of the tectonic plates. It has been his integrity which has sustained the scientific quality of the research in the NASA Geodynamics program, his hard work and dedication which have been so important in gaining the funding support for this work. Above all, this volume is dedicated to Tom for his diplomacy, his understanding, and his sense of humor.