Look at VLOOKUP:

On first sheet in B2:

=VLOOKUP(A2,Sheet2!$A:$B,2,0)

Where A2 = ID
Sheet2 columns A & B contain ID and Address

The 2 indicates return data from second column in range i.e column B

Copy down as required

HTH


"Krista" wrote:

I've got two columns of unique ID's. I need to match these unique IDs in the
same rows including another column with the data that I need in that column.
Basically I've got a spreadsheet with rows of contacts and another
spreadsheet with the email addresses for these contacts; however, the rows
don't automatically line up. Both tables have this unique ID, but need to
match them in order to put the email address in the correct contact row. Any
ideas?

TIA!
--
Krista