Shelbs, it starts off with them discussing about the company. Then they have a one on one interview, then they decide who makes it through. At my AD, only less than half made it through. After the unsuccessful people leave, they gave us group activities and that was it for the day. If you're successful, you receive an email in a week or two, with a link to the online assessment. If you pass that online assessment you move on to reference checks (: which is where I am at right now (:
Good luck on your assessment day!
nbailey073 what base are you going for ? How long ago did you have an AD?