Update Field Changes To Table Field

Hi,

I have a parts table with a field that holds a vendor's name which is selected from a combo box on a parts form. I've just noticed that if a vendor name is changed on the vendor form the field in the table isn't updated. I now have to go through all parts to adjust any changes done to the vendor name. Is there a way I can automatically update the vendor name in the parts table if there is a change done to the Vendor name in the vendor table?

Thanks