combining excel lists
 

Hi,
I have a large master list of data. Each piece of data within the list
consist of a unique identifier(ex. A1) with many other descriptive cells
(A2, A3, A4.....). This master list is edited weekly. When I receive a new
large list of data, I would like to rows from the new list with edited rows
from the master list based on the common unique identifier.

any suggestions?
thanks
dan