E-mail has transformed the way the world communicates and does business. It also has become a highly sought-after form of evidence in white-collar criminal and regulatory investigations. As an increasing percentage of business communication is entrusted to e-mail, conversations that once passed and vanished over telephone lines or on readily discarded fax pages, now lay preserved for years—often unbeknownst to their creator—electronically chiseled into a server, hard drive or back-up tape. A stored e-mail has the potential to provide an investigator with a trove of information, from the text of a past conversation, to the substance of attached files, to a catalogue of recipients and copied parties. For the government investigator, stored e-mails have the ability to narrate past crimes or regulatory violations and identify co-conspirators through frozen-in-time communications with a clarity and ease that was unimaginable a short time ago.