Satellite observations provide a reference frame for terrestrial survey whose origin is within one metre of the center of mass of the earth, whose z-axis is parallel to the CIO pole to the equivalent of five metres at the earth’s surface, and whose scale has an accuracy of about a part per million. A convention needs to be adopted to define the longitude origin. A well adjusted terrestrial network can be transformed to this system to about one-metre accuracy. Densification of the terrestrial network can be accomplished to 1.5 metre accuracy with the use of less than four days of Doppler observations for each site.