“After the customer has registered for future emails, downloaded your whitepaper, or entered your sweepstakes, there often is nothing to enhance that relationship. Companies need to think about what should happen next,” says Jeanniey Mullen, partner and director of email marketing at OgilvyOne Worldwide.

Ogilvy’s research shows the first three emails are the most critical. Mullen advises there should be an introductory message in which customers accept an invitation and give permission for future communications, followed by a second that sets up customers’ expectations by explaining future benefits (discounts, coupons, or high-value informational newsletters). The third should begin to deliver on their expectations by sending the promised newsletter, whitepaper, or discount offering.