Overview of Grid Data Files and Datum Shift Issues
Concept Procedure

You can do the following with grid data files

To do this... See this topic...
Set up a new grid data file Grid Data Catalog (GDC) Files
Specify a new grid data file for the United States Grid Data Files for the United States
Specify a new grid data file for Australia or New Zealand Grid Data Files for Australia and New Zealand
Use the high accuracy GDA94 datum for Australia Australian Datum Transformation and Coordinate System Changes
Specify a grid data version to resolve differences between source and destination coordinate systems for Canada Datum Shift Issues for North American Users
Modify a coordinate system file Coordinate System Files