As toolic said, use an XML parser. But, in general terms, when I want to use a regex to change an unknown chunk of text that sits between two known chunks of text, I do it backwards from what you tried to do here. Instead of capturing the part I want to replace, I capture the parts I want to keep, and keep them. For instance: 

$string = 'blah blah blah <some_sort_of_tag>CHANGE ME</some_sort_of_ta
+g> blah blah blah';
$newtext = 'I AM NEW';
$string =~ s|^(.*<some_sort_of_tag>).+(</some_sort_of_tag>.*)$|$1$newt
+ext$2|;

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Aaron B.
My Woefully Neglected Blog, where I occasionally mention Perl.

In reply to Re: regex: Need help substituting by aaron_baugher
in thread regex: Need help substituting by the_perl

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