E-mail — the main stop on the information superhighway — can be a blessing or a curse.

It was a curse to Harry Stonecipher, Boeing CEO, who was ousted when a female employee revealed through e-mail an illicit affair. It was a curse to Goldman Sachs when the company paid $2 million to settle federal regulators’ charges for improperly offering securities through e-mail. And it was a curse to Enron when sensitive e-mails ended up in court as part of a congressional investigation.

According to Jean D. Sifleet, business attorney and author of three books, “Many companies think that having an e-mail policy is enough to protect them from legal exposure. That’s just not realistic. Employees use e-mail for all sorts of activities, and they need to be trained about what’s okay and what’s not okay.”