Hi, i think, that many scripts exist to compare arrays or strings. In my version i use object "System.Collections.ArrayList", that gives a good performances for great sets. Test it and form your own opinion. Explanation you find in function-header. EDIT 14.10.2008 - now using Default and Opt("GUIDataSeparatorChar") for $Delim - fixed a bug by using @CRLF as separator #include <array.au3> Local $1 = '1,1,2,3,3,3,4,4,5,6,7' Local $2[10] = ['5','5','5','8','8','9','12','12','3','1