Introduction 

The ISDE6 will be held from 9 to12 September, 2009 at Beijing International Convention Center, China. The symposium will celebrate its 10^th anniversary since the promulgation of Beijing Declaration on Digital Earth at the First International Symposium on Digital Earth (ISDE) in 1999 in Beijing. The 2^nd to the 5^th ISDE were held in Canada (2001), the Czech Republic (2003), Japan (2005) and USA (2007) respectively. The amount of participants at these events was over four hundred, and the sponsors & exhibitors have been steadily increasing.

The ISDE6 with the theme "Digital Earth in Action" will play a crucial role in promoting international exchange and cooperation in building and developing digital earth theory, its frameworks and technologies; digital earth application, digital earth for global environmental change, earth observation technologies and other relevant fields. The symposium will review the achievements in digital earth and discuss the developing tendency of digital earth through the invited keynote speeches, special sessions for the 10^th ISDE anniversary and several parallel sessions.

As an important part of the symposium, the technical exhibition will be held from 9 to 12 September, 2009 at the symposium venue. The technical exhibition will show the technical achievements of each enterprise and the up to date products both in hardware and software. The exhibition will bridge between science and technology, technologies and applications in the field of advanced earth observing systems, remote sensing and global positioning system, virtual reality and visualization, high-performance computation and simulation, integrated geo-informatics technology, spatial data analysis and management, and in many other application fields.

The 10^th anniversary symposium on Digital Earth will be a major opportunity for foreign companies to enter into this Hi-tech market in China. Meanwhile, Chinese companies can show their products and services to many international participants and overseas exhibitors. It must be a very welcome event.