Try this:
On sheet 1:
A1: (ID num)
C1: =VLOOKUP(A1,Sheet2!A:B,2,0)

Does that help?

***********
Regards,
Ron


" wrote:

I have 2 worksheets - Sheet1 contains a list of ID numbers in column A,
contact names in column B. Sheet2 contains a list of ID numbers - some
of which will match those in Sheet1, with email address next to them.
I want to create a formula for Sheet1 which will look at the ID number
in cell A1 in Sheet1, search in Sheet2 for the corresponding ID and
bring the relevant email address forward into Sheet1. How do I do this?