Whether e-mail is clinically addictive or merely figuratively so is in dispute. That it encourages obsessive behavior isn't. The average American e-mail user checks his or her inbox five times a day, according to AOL. What smart marketer doesn't want to be where customers fanatically look?

Sierra Trading Post, a seller of discount apparel and outdoor gear, in Cheyenne, Wyoming, started its e-mail program in 2001 as a way to move clearance items. Today it advertises several sales a month, including the occasional e-mail exclusive. The company, with more than $100 million in annual revenue, narrowly slices the audience for its mailings based on customers' buying history. Highly targeted campaigns have achieved open rates, the percentage of e-mailees who actually open the message, as high as 35 percent and conversion rates, the percentage of recipients who buy something, of 5 percent to 10 percent, says Marc Angelo, Sierra's online marketing manager.

For companies looking to emulate that level of success, one of the best resources is Email Marketing Reports, edited by independent journalist Mark Brownlow. He recently spoke with Inc.

What are the main e-mail marketing strategies?

Most e-mail programs are designed for one of two purposes. Promotions are normally short, punchy e-mails with images; they encourage the recipient to take immediate action, such as a purchase, a download, or an information request. Newsletters are information-rich and look to build trust, credibility, and long-term relationships. You can mix and match the two, of course.

Should businesses buy lists of addresses?

With few exceptions, these lists are scams or have already been e-mailed to death. A better option is to rent a list using a reputable list broker.

How do you build an e-mail address list?

Consider every contact point with customers and prospects as an opportunity to invite them to sign up for your e-mail program. Reassure customers about their privacy and let them know how often they can expect to hear from you. Finally, consider offering a sign-up incentive relevant to your target audience.

When is the best time of day or day of the week to send e-mail?

Take published stats on e-mail responses by time of day and day of week with a pinch of salt. They can help guide your thinking but may draw from campaigns that bear little resemblance to your own. Instead, consider when your target audience will most likely have the time and inclination to read your messages.

How often should I sende-mail newsletters?

E-mail at least monthly and no more than twice a week, unless you have good reason. If you e-mail often, watch your results carefully to see if people are getting turned off.

How do you stay off e-mail blacklists?

Send e-mail only to people who request it, and send them only the information for which they specifically asked. Check your delivery reports, and remove any addresses that show permanent errors. And run your content through a spam filter preview tool provided by your e-mail marketing service to catch any problems.

Using your e-mail newsletter delivery report, watch your "open rate," the percentage of people who open an e-mail, for your entire list and for key subgroups of customers. Just don't get obsessed: As more systems block the technology used to record an open, rates will fall across the board.

  • To get a sense of what your website looks like on a cell phone, go to www.Skweezer.net.