expression.Save
expression Required. An expression that returns one of the objects in the Applies To list.
Remarks
If the publication has not been previously saved, calling the Save method is equivalent to calling the SaveAs method with the FileName argument set to the value of the publication's Name property. If the publication has been previously saved, the Save method will save the current version of the publication in the format in which it was opened and in the location to which it was last saved.
Calling the Save method always performs saves in the foreground regardless of whether background saves are enabled.
Example
This example saves the active publication if it has changed since it was last saved.
If ActiveDocument.Saved = False Then ActiveDocument.Save