Direct email marketing (EDM) is a format for email-based campaigns in which standalone advertisements are sent to a targeted list of recipients. The messages, which may be text, HTML, or rich media, look like Web-based ads rather than typical email messages. A number of elements make direct email marketing different from spam or other less sophisticated email campaigns. For example, the sender may use customer segmentation techniques to ensure that the message is appropriate for the group it's sent to, and use personalization techniques so the recipient is addressed as an individual.

In contrast to the bombardment approach of spam, the concept behind direct email marketing is that it makes more sense to send attractive, professional, and compelling ads to a smaller group of recipients that might actually be interested in receiving such messages. Direct email marketing is generally permission-based opt-in email, rather than unsolicited commercial email (UCE).

Direct email marketing messages often include mechanisms that provide the sender with feedback on the effectiveness of a campaign, by making it possible to track metrics such as the number of messages that were opened, the number of clicks that were generated from a message, the number of recipients that requested removal from the sender's list, and the number of messages that were bounced by the recipient's server.