Technologies designed specifically to track and monitor human beings have been in development for at least two decades.
In the virtual realm, software programs are now capable of watching us in real time, going so far as to make predictions about our future behaviors and sending alerts to the appropriate monitoring station depending on how a computer algorithm flags your activities. That is in and of itself a scary proposition.
What may be even scarier, however, is what's happening in the physical realm. According to researches working on human-embedded microchips it's only a matter of time before these systems achieve widespread acceptance.
Your initial reaction to this idea may be one of disbelief. There's no way society would accept such a device. Why would anyone want to implant this in their body?