From my recollection, if your ground transfers are through Disney, You put you tags on at home, and they pick up and transfer your bags in Orlando. From what I remember, those same tags stay on your bags and they transfer them from your resort to the ship. The night before you get off the ship, they give you new colored tags. They then transfer your bags to the area of the cruise terminal that corresponds with the color of your tag. Anybody who has been more recently, correct me if I am wrong or it has changed. (Of course the last time I went was pre-9/11, and it may have all changed since then).