The new Lanai Staterooms recently installed on Veendam feature a sliding glass door that opens onto the wrap-around exterior promenade deck. The doors automatically close when the doorway is clear — much like an elevator. For those concerned about privacy, the doors are mirrored.
The lanai door has its own key that is separate from the stateroom key that is also a charge card and ID. When we visited the ship, they had just received a shipment of brand-new teak deck chairs that were still in their boxes.