Another option with TT is to use the WRAPPER setting.

my $tt = Template->new(WRAPPER => 'wrapper.tt', ...);
$tt->process('whatever.tt', ...);
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You then put your header/footer code into wrapper.tt and, wherever you want the body content to appear, insert [% content %]. If the header/footer are in separate files, as in YourMother's example, wrapper.tt would be:

[% PROCESS header.tt %]
[% content %]
[% PROCESS footer.tt %]
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