Book excerpt: Geodesy has undergone technological and theoretical changes of immense proportions since the launching of Sputnik. The accuracy of current satellite geodetic data has approached the centimeter level and will improve by one or two orders of magnitude over the next decade. This bodes well for the application of geodetic data to the solution of problems in solid earth, oceanic and atmospheric sciences. The report Geodesy in the Year 2000 addresses many areas of investigation that will benefit from this improvement in accuracy.