Dynamic Updates on Compiled Worksheet
 

I have no idea where to begin looking for this solution, but am confident
Excel and its users are capable of this. I am using Excel 2003 on Windows XP.

Sheet1 is a complete list compiled from items listed on sheet2, sheet3, etc.
What I need to do is remove items from sheet 1 that have a value placed in
column 3 or column 4 of sheet2, sheet3, etc.

I believe that the current sheet1 list was compiled from simply
copy-n-pasting the other sheets, but sheet1 can be rebuilt (i.e., paste link)
if need be.

Thanks you in advance for your assistance.

Regards, Bill