When acquiring customers, you want to find people who will buy from you and stay for a long time. In many cases, it is hard to make a profit from consumers who buy once and never again. In fact, many marketers don't consider a one-time buyer to be a customer at all — customers are those who have purchased from you two or more times.

So what should you offer to consumers to convert them into long-term loyal customers? It seems to me that there are five basic ideas that you should convey to them:

First, that you have a superior product or service. Consumers want to know why your product is the best for them. What special features can they take pride in owning? How was it made or how do you use it to produce great results? Product differentiation has always been a goal of successful advertising. This is why there are a dozen brands of laundry detergent still on the market today with loyal followings.

Second, that your company stands for something. Brand is still popular with consumers. People like to identify with a brand — my BMW, my Crest toothpaste, my Kraft Crystal Light. Brand building is worth it, if you use it to acquire long-term loyal customers.

Third, that you have excellent customer service. Today companies have not just toll-free numbers but Web sites that accept comments and e-mails. Who would want to buy insurance, or deal with a bank or phone company that did not have really good and accessible service?

Fourth, that millions of others are buying your product. People like to think that they have made the right decision in buying from you. There is always the herd instinct. If you can get across to consumers that they are not alone in choosing your product, you have won half the battle.

Lastly, express that you are constantly improving to keep up with the times. Do you have an R&D program? Tell consumers about it. Tell them the new features that you have added recently. People like to feel that they are modern and up to date. They buy the latest products with the latest features — from a long-established, reputable company.

So how can you get these messages across? Mass marketing messages work, if you are big enough to afford it. If you are not, we now have the Internet. One of the most powerful communication methods today is the personalized promotional e-mail. Companies today are building customer marketing databases to which they append scores of fields of relevant data. Using those data, you can create segments and design marketing strategies for each segment.

When customers become one-time buyers, you get them to provide their e-mail, with permission to contact them about your products and services. At this point, you can put them into segments, and send to consumers in each segment communications that speak to their lifestyle and interests. Now is the time to explain your five basic ideas. Your messages to seniors will be different from those sent to college students, or to families with young children.