In today's digital economy, data enters and leaves enterprises' cyberspace at record rates. For a typical enterprise, millions of emails are sent and received and thousands of files are downloaded, saved or transferred via various channels or devices on a daily basis. Meanwhile, enterprises hold sensitive data that customers, business partners, regulators, and shareholders expect them to protect. Unfortunately, companies constantly fall victim to massive data loss and high profile data leakage involving sensitive personal and corporate data continue. Data loss could substantially harm a company's competitiveness and reputation, and could also invite lawsuits or regulatory crackdown for lax security. Therefore, organizations should take measures to understand the sensitive data they hold, how it is controlled, and how to prevent it from being leaked.