Types

Most email monitoring takes place in a workplace environment, where a company monitors the email of its employees. Another type of email monitoring is illegal monitoring, where a virus or trojan sits on your computer and records everything that you type.

Time Frame

With the right software in place, email monitoring can occur instantaneously and transparently. As emails are sent, they pass through monitoring software, which looks at their data and then passes them along without the email user's knowledge.

Identification

It is extremely difficult--and in many situations impossible--to detect email monitoring, because the type of software that is used to perform the monitoring does not leave traces of itself in the emails.

Misconceptions

Although many people believe that workplace email monitoring is illegal, so long as your company has an established policy in place that permits them to do so, employers are legally allowed to monitor your email communications.

Warning

If you believe your email is being monitored, you should take caution with what you write and send, as someone could read and use the information that you are sending.

Source:

Is Email Monitoring Legal?

Monitoring Employee e-mail