It's worth having a look at what others have done.
This set of Case Studies shows how email was used successfully for marketing, customer relationships, and information management.

A international travel company had collected individual email addresses when customers had booked but they hadn't cleared sending email promotions to them. Their first colourful HTML mailing said "I hope you don't mind us contacting you"; featured an attractive holiday offer with a prize competition and a promise not to contact the recipient again unless they responded and agreed to receive future emails.

The response rate was about 18%. Very high for unsolicited email. This gave the company a base of opt-in customers. They used this base to get some experience of email and to build a profile of the recipients.

Then the company launched a promotion on their website offering accomodation for Free Weekend Breaks (guests had to purchase meals) to new customers who registered on their website and who agreed to opt-in to receive travel updates. Customers filled in areas of interest when they registered, plus they were given the opportunity to email up to nine friends with the offer. By the end of a month the site had 250,000 new opt-in subscribers - more than twice the number the company was aiming for.

A wine company started sending out an email newsletter. At first they didn't differentiate between customers but sent everyone the same newsletter. Over time, the company began to use its database to create customised newsletters based on past purchases or the price range of wine purchased. This more customised approach resulted in a doubling of the revenue from each newsletter.

A US medical site recently launched a newsletter for people suffering from a particular disease. It featured news, reports, tips on disease management, recipes etc. Consumers register for subscription on the portal website which covers a wide range of medical conditions. Because the newsletter contains useful content that the target group wants to know about it has been achieving unique visitor click-through rates of nearly 30% and total click-through rates of more than 80%.

A large US department store sends 12 to 15 email messages annually to each person on their customer email list. These are people who have signed up to receive regular updates from the store when they visited the web site. The emails are targeted to the recipients interests. They can unsubscribe at any time. The customers who click through to the website from these emails buy on average five to seven times more frequently than other visitors to the site.

A fashion retailer has two types of opt-in email list. The first is for people who have requested a weekly (Thursday) early access message as to the week's sales items, which are posted to the public on Friday noon. The second type of email goes approximately monthly to distinct market segments, informing recipients of new products or promotions. The store analyses purchase and demographic information to customise the mailings. For those who have not bought online, the store sometimes sends a price-off email coupon. Because the cost is so much less than traditional direct mail the store can easily vary its offers to different groups of customers.

A hand-held computer maker communicates regularly with their market through email. When the programme began, 25 percent of the customer base said they were interested in receiving email tips on product use and marketing information. Customers instruct the company on their web site, what kind of communications they want, and how often they want to be emailed. The company stays in touch with its customers and can promote their newest updates and new products to them while helping them with information about how to get the best use from their purchase. Because the company adds value to its communications, consumers don't resent the marketing information. They regard it as a trade-off.

A IT company launched a new website using email. They achieved a 20 percent click-through rate to the site and a conversion rate of 2.5%. Four months later they sent out another similar mailing but this time they added an offer of a free white paper on a subject of interest to their market. Their response rate jumped to 35% with a conversion rate of 6.5%.

A company that matched freelance workers with companies needing additional help had been using web advertising banners to try to drive people to their website. But they weren't getting enough customers. The banner click-through rate was less than one-half a percent! They started using personalised, opt-in email, in which each recipient was addressed by name. The recipients could click straight to the site to view work opportunities in their field. 10% of those who received the first email clicked through to the site. They also emailed an opt-in newsletter to the registered users (employers) telling them of site improvements.

The conversion rate of those that clicked through was 15% and the dollar value of company projects listed on the site rose 16 times from $15 million to $250 million within a month.

Five years ago the owner of a florist business in a secondary centre figured out that two thirds of her business came from approximately 20% of her customers. Applying classic one-to-one marketing techniques she decided to concentrate on maximising the business from her most valued customers. She captured data from her customers (with their permission) so that she knew what their needs were. With this data she was able to establish who her most valued customers were and which customers had the potential for growth. She started using direct mail to remind them of upcoming floral occasions like birthdays and anniversaries and to offer them special deals. With the growth of the internet much of this contact is now carried by email. She has almost doubled her customer base in two years and her revenue has risen by 25% each year. She doesn't use traditional advertising and she doesn't have a web site. Yet she gets around 15 new referrals a day from her existing customer base.

It's not always necessary to send a newsletter or a promotion. Sometimes a simple "How's it going ? Everything OK? " email from the CEO can work wonders in encouraging loyalty. Jeff Bezos at Amazon.com is very good at this. Another effective way of showing you are thinking about a customer's needs is matching up your online and offline offerings. For example if you have a printed catalogue as well as online offerings, send that to your online clients. They may continue to order online but you are reinforcing your brand and their loyalty by providing them with offline browsing.