hmm .. what exactly are you working on? .. a normal web site? can you show any examples of what you're talking about?
i could take a guess at what you're trying to achieve, but it would probably be way off cause i'm not certain what you're talking about.
Maybe you're in need of a templating system, or maybe you're just looking for an alternate way of doing things? There's a million ways to architect re-usable headerr/nav/footers in a site, ... here's one very simple example.
includes/global_header.php
PHP Code:
<html>
<title><?php echo $page_title; ?></title>
<body>
<h1>My Cool Site</h1>
<div class="nav">
<a href="/">Home</a>
<a href="some_page.php">Some Page</a>
</div>
includes/global_footer.php
PHP Code:
<br />
© 2008 All Rights Reserved
</body>
</html>
some_page.php
PHP Code:
<?php
$page_title = "Some Page";
include 'includes/global_header.php';
?>
This is some page ...
<?php
include 'includes/global_footer.php';
?>