[synth3tk]

If you really want to get advanced, you could do this with PHP (assuming you're using PHP instead of straight HTML).

Create a file named "header.php", then use a php include to pull that "header.php" in every page (you've got to put the code on each page).

The benefit is obvious: make changes to header.php, and it changes on every page that calls it, across the site. Another benefit is that you won't run into pesky frame issues.

But I don't know what you're using to edit/publish this site, so the above may not work for you.