The rear passenger's side power window is not working.
If the window is not working at all, the switch, wiring, or motor is likely bad. I would recommend having your window system inspected by a professional. This inspection will consist of looking up the wiring diagram for the window and testing for battery voltage at certain locations throughout the circuit. Once the loss of power source has been determined, this will reveal to the technician which part(s) will require replacement in order to fix your window. If the window is stuck up, this problem can be resolved at your convenience. If the window is stuck down, I would recommend having the repair done as soon as possible as the security of your vehicle will be at risk with a stuck open window.