If you aren't aware of what the background of this picture is, it's the Vietnam War memorial in Washington, DC. On memorial day, no less. I took my camera and wandered Arlington national cemetery and visited some of the memorials for the day. This is one of the many interesting things I found. This shot isn't staged, it's just the way I found it.
 
Photographically speaking, the rule of thirds comes into play here via the recruiting poster. The base of the shot is well framed by the flowers and base of the memorial while the flags drag your eye around the image. There's a good amount of negative space here too--the memorial itself.