one editor for Word documents?

[that guy]

There are a group of people that work at my office that write Microsoft Word documents as a group, but they want to set it up so that while anyone can make changes to the document, there is only one editor that can accept those changes. Is this possible? They are using Microsoft Word 2007.

If this isn't possible in Word 2007, is it possible in Word 2010? If not, is there any word processing software out there that allows a group to make changes to a document, but only has a single editor that purviews those changes, and decides what makes it into the final draft?

Thank you for any help you can provide!