A door system for a passenger vehicle includes a door, a first movement stage, a second movement stage, a second movement stage, and a movement transfer system. The door includes inboard and outboard door panels, and an inner door structure disposed in a cavity defined between the inboard and outboard door panels. The first movement stage moves the door outboard and inboard to open and close an opening of a vehicle body. The second movement stage moves the door forward and backward relative to the opening. The movement transfer system mechanically links the first and second movement stages to cause simultaneous movement of the first and second movement stages. The first movement stage is coupled to and extends between the vehicle body and the second movement stage. The second movement stage is coupled to and extends between the first movement stage and an inner door.