Try something like this:
=IF(B1="yes",INDIRECT("'"&$A1&"'!X1")+IF(B2="yes",INDIRECT("'"&$A2&"'!X1")))
>I want to create a formula with variable sheet names based on the contents
>of
[quoted text clipped - 11 lines]
> Any help would be greatly appreciated.
> Mike
Use INDIRECT to resolve the variable sheetnames* in A1:A2 ..
Place this in say, C1:
=IF(AND(B1="yes",B2="yes"),SUM(INDIRECT("'"&A1&"'!X1"),INDIRECT("'"&A2&"'!X1")),"")
The expression will return "nothing", ie:"", as the value_if_false (you
didn't specify this in your post). Note that we have to use double quotes for
text:"yes" (not 'yes').
*Ensure there's 100% consistency between the actual sheetnames and the names
entered within A1:A2 (check for possible typos, extra white spaces, etc if
you get #REF!)

Signature
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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> I want to create a formula with variable sheet names based on the contents of
> a cell.
[quoted text clipped - 10 lines]
> Any help would be greatly appreciated.
> Mike
Max - 25 Aug 2006 08:31 GMT
Clarification:
> *Ensure there's 100% consistency between the actual sheetnames
> and the names entered within A1:A2 ..
Except for case, that is (ie it's not case sensitive)

Signature
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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