IT departments regularly have the ability to see exactly what you're doing. In fact, lots of software out there lets IT officials watch on their monitor, in a smaller window, exactly what you see in your monitor as if they were sitting next to you watching with you. I read about a software/hardware combo that projects up to 30 or so miniature windows, through the use of a visor, in front of a technician for him to monitor simultaneously. I don't think it ever caught on, but one company was trying to get that started.
But, yes, you can monitor anything on a network, including things done even on a single system, not related to the network at all.