...you have to forget "Header" for a moment - that seems to be a bit of a red herring. Do you want to insert information from a file (your "header" file) to some other files so that when you update information at that "Header" file, the inserted information get updated automatically ? If so, check out "Help" at Word. Use the "Index" help and type in Link. I think what you are looking for is in there.

Lots of information also available if you put OLE at Google.