One possibility is illustrated in this sample construct:
http://www.savefile.com/files/609942
Summarizing multishts by key col n col header.xls

In the summary sheet,

Lessor Table
Create a DV droplist in C2 to allow selection of col header of
relevance/interest, eg; Acres, Acreage
List the source sheetnames in C3:E3, eg: X, Y
List the lessors in B4 down

Core extract formula
In C4:
=IF(OR($B4="",C$3=""),"",SUMIF(INDIRECT("'"&C$3&"' !A:A"),$B4,OFFSET(INDIRECT("'"&C$3&"'!A:A"),,MATCH ($C$2,INDIRECT("'"&C$3&"'!1:1"),0)-1)))
Copy C4 to E4, fill down to populate.
(A "Totals" col can be placed at the end)

Similar construct can be made for the Lessee table
(illustrated below the Lessor table in the sample)
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
---
"Scafidel" wrote:
I would like to create a summary worksheet at the end of my workbook that
would add all the Acres (see below) of each Lessor on all worksheets. Each
sheet of the workbook contains information like below. Each Lessor is on one
or more of the app. 100 sheets, as are Lessees.
Lessor Acreage Interest Acres Royalty Lessee
Joe 100 0.25 25 0.125 Humble
Sam 200 0.75 150 0.125 Gulf
Edd 80 1.00 80 0.125 Gulf
Mac 640 0.50 320 0.125 Humble
I would like to make a summary sheet that be similar to the other
worksheets, but with totals of all worksheets of the workbook by each Lessor
and/or by each Lessee.
Thanks
Jerry