Telephone monitoring tends to be more targeted in nature, because it is hard to set up electronic programs to automatically detect or record communication for all employees. It is the easiest type of monitoring for a manager or supervisor to do, as it can be done simply by picking up extension lines that are easily installed and accessible.

The most important thing to realize is that if an employer is tapping your phone, the listener is required to listen in only as long as it takes to determine if the call is of a specific business nature. The person is not allowed to listen in on private conversations. However, what constitutes a private conversation or not is subjective, and is often decided in court. What's important is to simply stay away from making private calls on business phones, especially where there may be specific monitoring going on for quality control or other purposes.