It could be all the Activate's, Select's, and screen updating causing
the memory consumption. The code you wrote could be condensed into:
Application.ScreenUpdating = False
SUWb.Sheets(SUName).Rows(FIRSTROW & ":" & FIRSTROW + nos).Copy
MasterWb.Sheets(Catg).Rows(FIRSTROW & ":" & FIRSTROW).Insert
shift:=xlDown
Application.ScreenUpdating = True
----
Nick Hebb
BreezeTree Software
http://www.breezetree.com