The Acer AL2223W monitor stand can tilt, swivel and have its height adjusted. It's a versatile monitor in that respect; you'll be able to use it in most environments. To adjust the height you'll need to unlock it using a switch on the back of the monitor.
Stand the monitor upright.
Face the back of the monitor and look for a lock switch at the base of the stand.
Slide the lock to the right to allow the height to be adjusted. Take care not to detach the monitor from the stand when you're adjusting it. When you've finished, slide the lock switch back to the left.