Basically, you switch houses with your neighbors for 48 hours and re-design one room of their home with $1000.00, one carpenter, one designer and all of the elbow-grease supplied by you, your spouse or friend, and the designer. Of course, you can't go back to your house until it's finished.
Then, you get to see what they've done to your once-lovely room and decide which things you are going to change immediately. Sometimes you cry, sometimes you laugh, sometimes you want to kill the designer.