=INDEX(Sheet2!A:A,MATCH(1,(Sheet2!B2:B200=100)*(Sh eet2!C2:C200=--"2008-07-02"),0)

which is an array formula, it should be committed with Ctrl-Shift-Enter, not
just Enter.
Excel will automatically enclose the formula in braces (curly brackets), do
not try to do this manually.
When editing the formula, it must again be array-entered.

--
HTH

Bob

(there's no email, no snail mail, but somewhere should be gmail in my addy)

"Christina Byrne" <Christina wrote in
message ...
I need to pull data from a 2nd spreadsheet with vlookup where my reference
is
not unique (there is a non unique numerical reference and a non unique
date
but combined these would be unique). I would like to combine a 3 digit
number
and a date to create a unique reference e.g. '100' and '01/07/2008'.
Is it possible to do this?
Or how else can I pull data from one spreadsheet to another when the
numerical references are not unique?