Your leads are gathered by offering something in exchange for the user’s email address.

It basically involves having your subscription offer listed alongside other subscription offers, and when someone signs up for another newsletter, they are given the option to signup for yours as well without having to re-enter their information a second time.

This is one of the easiest methods to building a targeted mailing list and takes very little effort. The leads are extremely targeted because you only pay when someone joins your list and see your offer.