Well it depends on several things. First thing is that Word 2007 saves documents in XML format and NOT the standard office 2003 .doc format. So getting theMicrosoft Office Compatibility Pack would be a great place to start. Then I'd also look at the fact that if both computers do not have the same font and/or printer installed, then you could also have some changes to the document. I guess if you're trying to format a document for publishing and want it to show correctly on another computer, then perhaps sending them a PDF version would be the best option. Again, printer specs and fonts can really play tricks on formatting.