ATG Outreach provides a feature that allows you to track whether or not the recipient opens the e-mail. Use the following code to insert the e-mail tracker:

<aco:trackOpenEmail/>

The option adds a hidden tag containing an image with information about the campaign, the stage, and the profile ID. When the recipient opens the e-mail, and if the e-mail client he or she is using is configured to display images, the tracking information is sent to the ATG Outreach server and logged to the database. You can then view tracking-related data in ATG Outreach reports (specifically, in the Opened column in the Email Campaign Details report).

For more information on this feature, refer to the ATG Outreach Administration and Development Guide.