This is to announce that the Intercommission Committee on Theory (ICCT) organizing international symposium: "VI Hotine-Marussi Symposium of Theoretical and Computational Geodesy: Challenge and Role of Modern Geodesy" will be held at Wuhan University , PR China, 29 May - 2 June 2006. The symposium will ocus on the following five topics:

Satellite gravity missions: open theoretical problems and their future application;

Earth-environmental, disaster monitoring and revention by Geodetic methods;

GNSS: Mathematical theory, engineering applications, reference system definition and monitoring;

Deterministic and Ramdon fields analysis with application to BVP, approximation theory and inverse problems;

Statistical estimation and prediction theory, quality improvement and data fusion.