Sitewide Header & Footer Includes || Trouble with Relative Paths..........

Hey All. Got a perhaps easy question here: How can I create a global header and footer include to my site pages where I don't rely on absolute paths to include and image files? I'm having trouble including my header and footer .inc's within a multi-level directory structure -- the relative paths to images (and to includes within includes) are not currently accessed within the current directory structure. I'm assuming I'll need to prepend all image and include files with a path variable that I set within each page, or something along those lines? Any help much appreciated, --Confused --