[Jeremy]

Thanks for that Chris - will look into it.

This is actually the way that I'm using it at the moment:

Obviously it's just an example, but I've seen odd behaviour when data from either array has regex or pattern type characters in them.

#!/usr/bin/perl -w


## This Array is the orginal data to be searched:
## Data in here may have regex / pattern characters.
open (FH, "$WorkingDir/FILENAME");
while (<FH>)
	{
		chomp $_;
		push(@Data_Array, "$_");
	}
close (FH);


## This Array contains the things we want to look for 
## in the Data_Array:
## Data in here may have regex / pattern characters.

open (FH2, "$WorkingDir/FILENAME");
while (<FH2>)
	{
		chomp $_;
		push(@Look_For_Array, "$_");
	}
close (FH2);

foreach $Data_Array(@Data_Array)
{
	foreach $Look_For_Array(@Look_For_Array)
	{
		if ($Data_Array =~ /$Look_For_Array/i)
		{
			$Data_Array =~ s/$Look_For_Array/$Something_Else/gmi;
		}
	}
}

Maybe I should be looking in Perl OP at:
# Quote and Quote-like Operators
# Regexp Quote-Like Operators

& using q somewhere may be the answer?