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Spread the Word with Mailing Lists (Web Techniques, June 2000)

Spread the Word with Mailing Lists (Web Techniques, June 2000)

Spread the Word with Mailing Lists

By Alan Schwartz

Email is the most powerful communication tool available on the Internet today, which makes mailing lists a prime marketing tool. Nearly everyone online receives email, and most people read it regularly. Messages are easy to create and inexpensive to deliver, even to people with low-bandwidth connections.

But taking full advantage of mailing lists requires forethought. Businesses must choose the right equipment or outsourcing company, build a subscriber base, learn to phrase informative messages, and track the effectiveness of their efforts. If you approach a mass-mailing project wisely, your care will earn you a more dedicated clientele and perhaps the opportunity to sell advertising to other businesses.

Mailing List Mechanics

As you probably know, a mailing list is a group of email addresses of people who receive the same messages. You send a single message to everyone, and your mailing list software sees that the message is delivered to list subscribers.

Mailing lists have been around nearly as long as email, and they're especially valuable to businesses. You can promote your business via email by sending out announcements, press releases about upcoming products, periodic newsletters, or updates on improved services, or even by hosting user discussions about your offerings. I'll focus on mailing lists designed to promote one-way communication from company to customer—but you can apply the ideas here to lists designed for communication among your customers (or your customers and your company) as well.

It's crucial to separate list content from list management. Most mailing lists do this by providing two email addresses: a list address and a request address. Messages sent to list addresses are intended for list subscribers; messages sent to the request address are intended for the people or programs managing the list (requests to subscribe, unsubscribe, or take other list-related action). This keeps list subscribers from having to wade through management requests to get information. Requests are forwarded either to the list manager or the person in charge of list operations, or are automatically handled by specialized mailing list management (MLM) software. (See " Online" for URLs of MLM products mentioned in this article.)

Your mailing-list name should immediately convey its objective. The list address is conventionally named for the list's purpose or for a relevant attribute of the intended audience. For example, if you're running an announcement list for your WebWidget product, the list address might be:

[email protected]


[email protected]

The request address is conventionally either the name of the list followed by -request—for example:

[email protected]

or the name of the mailing-list management software itself (for example, [email protected]).

Subscribers for Your Philosophy

Planning a mailing list strategy begins with determining the list's audience. Who are your subscribers, and what will their needs be?

There are three common ways to populate a list with subscribers. Address-harvesting methods collect email addresses from other (possibly related) mailing lists, newsgroups, or Web pages, and subscribe these addresses to your list. Harvesting doesn't provide subscribers with a choice until they receive the first list message, and doesn't assume any preexisting relationship with new subscribers. Although harvesting can provide a large number of email addresses, it's widely considered unethical and disreputable. Indeed, engaging in unsolicited commercial email—popularly called spamming—is one of the fastest ways to earn a poor reputation with Internet users. I strongly discourage companies from harvesting.

Only slightly better than harvesting is opt-out subscription. In this model, you populate your list with the addresses of anyone who takes part in a transaction with your company. This is an improvement over harvesting, because you do have somewhat of a relationship with these people, but it still puts the burden on the subscriber to request removal from your list.

The best method of populating a list is opt-in subscription. In this model, you offer your customers the opportunity to join a mailing list. You either provide instructions for subscribing through email, or offer customers a way to express their interest and provide their email addresses at your Web site. If the mailing list provides information that customers value, they'll stay subscribed, and your company will have a powerful avenue for marketing to them.

Nuts and Bolts

Running your own mailing list server needn't be expensive or difficult—but if you expect to send frequent mailings to large lists, make sure that your hardware and software are up to the job. Although this is mostly a problem for high-traffic discussion lists, even monthly announcement lists can tax a system if there are tens of thousands of subscribers.

Of course, a fast Internet connection is the top priority for a mailing list server. The most popular operating systems for running mailing list server software are UNIX and Windows NT. Thanks to Linux, a relatively inexpensive PC can host large announcement mailing lists very comfortably. In general, mailing list servers don't require much disk storage, but memory and CPU speed become increasingly important as the size of the list increases. For a list with about 5000 subscribers receiving one message per week, a dedicated Pentium II-based Linux system with 32MB of memory is plenty. For a daily mailing to 100,000 subscribers, I'd recommend a Pentium III system with at least 128MB of memory. With such a high mailing volume, your mailing list software will almost certainly need to spawn multiple copies of itself to deliver all of those messages in parallel and in a timely fashion. The list server can also be run on your Web server or other Internet host, with a commensurate increase in processing power and memory.

Although the mail software distributed with Linux (typically, the sendmail, qmail, or exim suites) already contains support for simple mailing lists, any serious use of mailing lists for marketing requires specialized MLM software. There are many different MLM programs for Linux, each with its adherents. The popular Majordomo package is a free Open Source MLM that excels at letting people manage lists remotely, but doesn't automatically remove subscribers when their email bounces. The more daring might look into listar, an Open Source and actively developed Linux MLM that takes a modular approach. Sites that use qmail as their mail transport agent usually choose ezmlm as their MLM software. Among the most powerful, flexible, complex, and pricey MLMs are the latest incarnations of CREN ListProc, which runs on UNIX platforms, and the venerable Listserv software by L-Soft, which runs on both UNIX and Windows NT platforms.

The same principles that apply to Linux-based hardware apply to Windows NT systems. Fast network connections and enough memory and processing power to handle large lists should be the primary considerations. In addition to Listserv, another popular Windows NT MLM is Lyris, which offers a friendly Web interface and is priced based on the maximum number of subscribers per list.

Favored Features

What should you look for in choosing MLM software? Naturally, you must first ensure that the software is powerful enough to meet your needs. Consider the number of people you expect to have on your lists, and how often you plan to send them messages. After you've ascertained that you'll have sufficient power, there are other important features for announcement lists to consider. All of the products I've mentioned so far provide these features:

Automated subscription and unsubscription with confirmation. Users should be able to subscribe and unsubscribe by themselves (unless you're trying to run a private list). Confirmation means that the MLM sends the would-be subscriber or unsubscriber an email message asking them to confirm their request; this prevents people from subscribing others to your list without their knowledge.

Support for restricting senders or moderated lists. When running an announcement list, you want software that accepts messages coming from you, but not messages coming from other subscribers. Most MLMs do this either by offering an option to restrict the list of valid message senders or by allowing you to designate the list as "moderated." Messages sent to a moderated list's address by a nonmoderator aren't distributed to the subscribers; instead, they are sent to the moderator, who can choose whether or not they should be distributed to the list. By making your company's spokespeople the only moderators, you ensure that only your announcements will be distributed to subscribers.

A Web interface for subscription and unsubscription. This provides an easy way for customers browsing your site to join or leave your lists.

Archiving. You may find it useful to have an MLM that can maintain an archive of the messages you send out, and allow users to search the archive for past announcements, especially if there's a Web interface for the search. Not only does this help your customers find past announcements, but they'll spend more time at your Web site if they can search your archives online.

Hired Hands

If you don't have the personnel or equipment to run your own mailing list server, another alternative is to outsource with a company that provides mailing list services. These companies typically provide a Web interface for subscription and unsubscription to your list, as well as archiving services. You don't need new hardware or personnel to set up and maintain the MLM software, but outsourcing often costs more over time. Most services charge either a per message fee or a flat monthly fee. If you want your own domain name (so messages appear to come from your company and not the company to which you're outsourcing) or a dedicated server that's used only for your lists, be prepared to pay commensurately more.

Lyris and L-Soft (maker of Listserv) offer an array of mailing list services. Another alternative is eGroups, which runs egroups.com and onelist.com. The company provides free list hosting if you're willing to accept someone else's advertising in your messages, and list hosting without outside advertising for a nominal charge. An intriguing feature of egroups.com is its ability to conduct online polls of list subscribers.

Email Eloquence

Once you have your list hosted by a list server and you've populated it with subscribers, what will you send them? Perhaps you'd like to announce your new product release, or your company's recent stock split; maybe you just want to keep your customers informed of new uses for your services. Whatever your goal, to take best advantage of email as a marketing tool, remember these principles:

  • When busy people open their mailboxes, they skim the subject lines first. Your subject line should be informative and should give the most important message up front. "We do it all for you," is a poor subject line. "New plug-in for WebWidget 3.0," is a good one.

  • Most people skim the text of a message to decide if they'll keep reading. Follow the journalistic principle of putting your most important information on top, to interest the reader and draw him or her to continue reading.

  • Be useful and recognizable. Naturally, you're more likely to keep subscribers on your mailing list if you provide them with information they care about. But it's equally important to use a similar style and layout for each announcement, press release, or newsletter that you send so that it becomes immediately recognizable as a product of your company. This can be difficult in the all-text medium of email, but it pays off in the long run.

If your mail client and your mailing list management software support MIME multipart messages (and nearly all do), you can send styled text in addition to plain text as part of a multipart message. For example, if you send your messages using Netscape Messenger, check the Formatting screen in the Mail & Newsgroups options, and be sure it's set to send messages in both plain text and HTML.

The mail composer should create two versions of your message. One contains only the plain text, and the other is written in HTML and preserves any typographic formatting you've made as well as any hyperlinks you've inserted in the message. The composer combines these two versions into a single multipart MIME message, and the subscribers' mail readers choose which part to use. A subscriber who receives the message in a mail reader that understands HTML (like Eudora Pro or Outlook) sees your styled message; one who reads his or her mail in a text-only mail reader sees the plain text instead. This lets you enliven your messages with emphasis and color, while still providing the information core for subscribers who don't use HTML mail readers.

  • Avoid using attachments. Attachments, including attached images, are slower to download and require more space for your recipients to receive them. Moreover, people worry about viruses in attachments, and you don't want them to associate that concern with your company. If you want to liven up the message with images, use a mail composer that can embed HTML <IMG> tags that point to images at your Web site instead. Netscape Messenger does an excellent job of letting you insert images as <IMG> tags rather than as attachments.

  • You should also limit your use of links. If you pepper your message with links, you'll dilute its impact and potentially confuse the recipient. Use links sparingly to provide more information about the content in the mailing, and position them where they won't disrupt the reader's visual progress through your message. For example, if each paragraph of your message details one of your services, add a single link at the end of each paragraph that readers can use to learn more. This placement keeps the link from interfering with reading the paragraph, and provides a consistent look and some visual separation between paragraphs.

    Email clients treat embedded URLs in various ways. Eudora and Outlook clients convert URLs into hypertext links, letting your readers click naturally and follow links in your messages. The AOL client, on the other hand, requires you to place HTML anchor tags around any URLs that you want linked. If you don't do this, your readers have to copy URLs from the email and paste them into a browser. This will severely cut down the number of click-throughs you receive from AOL users.

  • Don't send too often; your messages lose impact if you inundate the customer. If you're using the mailing list for announcements or press releases, the timing of the announcements largely determines that of the messages. If you're sending a regular newsletter, limit missives to once every two to eight weeks—often enough to keep subscribers thinking of you, but not so often that they're thinking of you as an annoyance.

  • Always provide your company name, the name of the mailing list, how to unsubscribe, and how to contact the list manager. The usual place for this information is at the very bottom of the message, separated by a row of dashes. When your subscribers change their email addresses, they'll want to know how to change their subscription address and who to contact if they have trouble.

Your Ad Here

If you've developed a regular newsletter, you've got an avenue for reaching your customers with information about your products, your services, and your company. But you may not be the only company interested in reaching these subscribers. By selling advertising in your email newsletter, you can recover some of the costs of running your lists. Selling subscriber addresses to interested businesses would provoke privacy concerns, but including advertising in your own mailings doesn't present such problems.

For plain text newsletters, simple text ads of about five lines are the accepted standard. Example 1 shows such an ad. If you're producing an HTML newsletter, there's opportunity to be more creative with your ads through the use of images and rich media.

How much advertising should you sell, and where should it appear? Third-party advertising should always be secondary to your own messages, so it should receive only a small share of your total message space and shouldn't upstage your company. A good rule of thumb is that no more than about 10 percent of the lines in your message should be third-party advertising, and most of that should be near the end of the message. Other positionings that can be effective without being overbearing include a one-line sponsorship statement and link right at the beginning ("Today's WebWidget newsletter is sponsored by Gizmocorp"), or information about related products or services placed near your own articles in the newsletter.

How'd You Do?

How will you know if your mailing list campaign is doing what you want? Even if your messages are reaching your customers, are those customers reading them and actively looking for more information?

One handy approach is to include hyperlinks in your messages and use your Web server log files to determine how many responses you're getting from your mailings. To be most accurate, use a different hyperlink in each message—perhaps by linking to a CGI script and passing a message identifier as part of the URL (for example, place your.company.com/news.cgi?msgid=20000311 in a message sent out March 11, 2000). A simple Perl script for logging click-throughs is presented in Listing 1.

You can search your Web logs for these message IDs to calculate your click-return on a given message. Other variations include message-specific promotional codes that subscribers can enter to receive special offers when they visit your site (this also helps you determine which messages are drawing the most attention).

Used properly, email mailing lists can keep your customers up to date, and give you a powerful and inexpensive avenue for disseminating information about new services and products. They should be part of any online marking strategy.

(Get the source code for this article here.)

Alan is an assistant professor of clinical decision making at the University of Illinois at Chicago, and the author of Managing Mailing Lists and coauthor of Stopping Spam, both published by O'Reilly and Associates. He is currently at work on his next O'Reilly book, Teaching Online.

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