From Excel:
Set a reference to the Word object library
Dim wdApp as Word.Application
Dim wdDoc as Word.Document
Set wdApp = New Word.Application
Set wd.Doc = wdApp.Documents.Open("C:\My Path\Mydoc.doc")
'additional code goes here
wdDoc.Save
wdApp.Quit True ' save any changes to the Word document
Set wdDoc = Nothing
Set wdApp = Nothing