As the previous post indicates, though you have reservations for a particular time, you still have to wait in line, some days longer than others. Then when you get to the desk you will be seated more quickly than those without reservations, but not necessarily at the exact time you requested. For example, though we had a 7 pm reservations, we stood in a long line for about 1/2 hour before getting to the desk, and were not seated until close to 7:30....to be fair, that was at the beginning of the cruise and we generally did not wait that long.