Instant Messaging (IM) is a well-established means of fast and effective communication. Once used primarily by home users for personal communications, IM solutions are now being deployed by organizations to provide convenient internal communication. This often includes the exchange and discussion of proprietary and sensitive information, thus introducing privacy concerns. Although IM is used in many legitimate activities for conversations and message exchange, it can also be misused by various means. For example, an attacker may masquerade as another user by hijacking the connection, performing a man-in-the-middle attack, or by obtaining physical access to a user’s computer.