Large (and small) government agencies deal with very sensitive information, from social security numbers to credit card information to personally identifiable information (PII) on a daily basis. Many of these agencies use written policies to attempt to prevent users from purposefully or accidentally sending or sharing this information in an unauthorized way. However, most of these agencies do not have technology in place to monitor and prevent this data from leaving their network and are completely unaware it is even happening. Something my daughters taught me from a popular red character on TV, 'Accidents Happen'. Even when people are being careful this old adage is true, accidents do happen. But these accidents can have huge consequences not only for the sender of the confidential data but the administrators and organization that allowed it to happen.
Read more at source: http://blogs.technet.com/b/govcloud/archive/2014/04/07/data-loss-prevention.aspx