Importance of email monitoring
Sensitive information today is crucial in ensuring it is kept safe and secure from external threats. There are different types of email threats. Company asset threat is a type of threat when someone from outside the company is posing as an authorised user and gains confidential data not available to un-authorised users. This can also be seen as sensitive information being released by a user from inside the company to users outside the company. Sending and receiving personal, none business related email is another type of threat; such as sending and receiving of pornography, abuse, and other generally none related business email and immorally not ethically correct. Usually having an email monitoring system in place reduces the risks of employees abusing the system. Internal staff will think twice not be sending each other inappropriate material if they knew emails were monitored and stored for legal reasons.
Whatever the threat, it is crucial a system is put into place, which monitors and protects against such threats. A good spam firewall with granular reporting functionality with message tracking would fulfil this. For example the sender and recipient of information sent can be identified and checked to see if they are authoritative to send such information. In any organisation different people will have different privileges to what they can send and receive. For example some organisations such as partner companies will have more trust than other companies. There may be a group of people that may be allowed to send executable attachments but to only a particular group of people within the company. So it is essential to know who is sending and receiving information and what the information is in order to know whether to allow the exchange to take place.
Wikipedia's guide to Email Tracking