The Asian-Pacific area, primarily the western Pacific boundary zone including China, Japan, and Southeast Asia, and the northern Indian Ocean boundary zone including the Tibetan Plateau of China and Southeast Asia, is the convergence zone of four plates: Eurasian, Pacific, Philippine and Indo-Australian. The region also includes a major portion of the tectonic system that is responsible for new activity in the Round-Pacific and the Alps-Himalayas mountain-building zones. The area is characterized by complex tectonics, violent crustal motion, frequent and fierce earthquakes, and devastating volcanic activity. In this area there is dense population, rapidly developing economics, and yet frequent and serious natural hazards (earthquakes, volcanic eruptions, sea immersion, etc.). Therefore this area is one of the most appropriate and urgent regions for research in tectonic and crustal motion, local deformation, sea-level change and their effects on the existing human environment. The main objective of the Asia-Pacific Space Geodynamics (APSG) Program is to unite all relevant activities in the region into a cooperative research project in plate tectonic, crustal motion and deformation, and sea level change in the area. This will provide a synergistic umbrella for scientists in the region to cooperate and to contribute to the better understanding of the processes involved and better prediction of major disastrous events. A major impetus for this program has been the emergence of space geodetic techniques with mm measurement capability.

Since the first observation of SLR/LLR in 1960s, almost half century has passed, and SLR is entering its second generation with higher precision. GPS has made dominate contribution on the monitoring of crust deformation due to its high precision, high data frequency and dense global distribution for its low cost and maintenance. Moreover, Galileo, GLONASS and Beidou systems join GNSS network and help us to obtain more data with higher precision. We are also pleased to witness the upgrading of the VLBI to its new generation, i.e., VGOS (VLBI for GGOS) fulfilled with VLBI2010 standard. All these progresses in space geodetic techniques provide us more opportunities to study the geodynamics of the global earth and regional (like Asia-Pacific region) geophysical phenomenon.  

The first International Meeting of the APSG was held in Shanghai in June 1996, and more than 2 decades passed, it is good time for us to review the progress of APSG and space geodesy, as well as the study of astro-geodynamics in Asia-Pacific region and beyond.