Joe
From Help on "Specifications"
Worksheet and workbook specifications.............
Worksheet size 65,536 rows by 256 columns
Sheets in a workbook Limited by available memory (default is 3 sheets)
See the rest of the Specs in Help for more info.
Also visit Charles Williams' site for info on Memory and Limits
http://www.decisionmodels.com/memlimits.htm
Gord Dibben Excel MVP