Well, I thought I would answer my own question... I have figured it out.
Yes, they can. You must just name is properly using the Define Name field
and refer to the other workbook.
thanks,
Mike

"Mike R." wrote:

Hi,
I have 2 workbooks that use a common data source which is a worksheet loaded
with name fields for validation lists. When I update some of the data source,
I need to update it in two places... is there a good solution so they can
share the data source with all the name fields? Any thoughts would be awesome!