Sheet1 has your list of reference numbers, from A2 to A100.
Sheet2 has the datalist, with the numbers in say D1 to D75.
NOW, if the names are in a column to the *right* of the numbers, say E1 to
E75, you could use the Vlookup() function.
Enter this on Sheet1, in B2:
=Vlookup(A2,Sheet2!D$1:E$75,2,0)
And copy down.
If, on the other hand, the names in the datalist on Sheet are to the *left*
of the numbers, say C1 to C75, then use the Index() Match() combination in
B2 of Sheet1:
=Index(Sheet2!C$1:C$75,Match(A2,Sheet2!D$1

$75,0))
And copy down.
You could of course use the Index/Match combo in the first case also, but
now you have exposure to different approaches.
--
HTH,
RD
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Please keep all correspondence within the Group, so all may benefit!
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..
Hi Mike
I thought I had this covered but it has not worked. I tried LOOKUP but it
just returned random names.
Thanks