The GGP is open to all organisations with access to the appropriate instrumentation, i.e. a SG. Each independent organisation that manages a SG will be called a SG group; there may be several SG groups in any one country. 

The GGP Agreements encourage SG groups to (a) upgrade existing SG facilities to a common standard of data acquisition, (b) participate in the 6-year observation period by maintaining the SG's in good operating conditions at fixed locations and (c) exchange raw gravity (and other important supplemental) data through high speed computer links. 

Funding for GGP activities is the financial responsibility of the supporting government organisations for each of the national SG groups.