I sat in a presentation once in which the topic of discussion was mission statements and vision statements. I've got to be honest, I still don't think there's much difference. As a matter of fact, a lot of time seems to be spent talking about what the actual difference is. It's kinda confusing.
Most companies have them though. Do you know yours? Maybe you do, maybe you don't but let me ask you this. Does it have any effect at all, on your day-to-day activities? Do you use it to help focus critical decision making? Not in my experience. Not even once.