The foundation for successful email marketing is a targeted, permission-based email list. Marketers call contact lists their 'goldmine' because it can generate much of their sales revenue. If you've built up a list of opt-in subscribers that are qualified and interested in what you have to offer, then you've completed the first step and are on your way. Now it's time to 'mine' for gold!

Below you'll find several list-building and retention ideas that will help you get the best results from all your email marketing activities:

1. Provide useful, relevant content. Your visitors will not give you their email addresses just because they can subscribe to your newsletter free of charge. You have to provide unique and valuable information that will be of interest or use to them.

2. Add a subscription form to every page on your website. Make sure it stands out so it is easy to find. If it doesn't look cluttered, you may want to include more than one on some pages. For instance, if your opt-in form always appears in the top-left corner of your site, you may want to add one at the end of your most popular articles.

3. Add subscription forms to your social media pages. Make sure that you don't waste this valuable source of revenue opportunities. Integrate your sign-up forms with Facebook and more!

4. Make it easy for readers to sign up. The more information you request, the fewer people will opt-in. In most cases, a name and an email address should suffice. If it's not necessary, don't include it here. You can always survey them once they're customers! We do recommend that you provide a link to your Privacy Policy however.

5. Publish a Privacy Policy. Let your readers know that they can be confident you will not share their information with others. The easiest way to do this is to set up a Privacy Policy web page and provide the link to it below your opt-in form. (Note: If you don't have one, put the words 'privacy policy generator' into a search engine and you should be able to find a suitable form to use.)

6. Provide samples of your newsletters and Ezines. This lets potential subscribers review your materials before they sign up to determine if it's something they'd be interested in.

7. Archive past newsletters and articles. An online library of past newsletters and articles is both appealing and useful to visitors and builds your credibility as an authority. In addition, if your articles are written with good SEO techniques in mind, they can increase traffic to your website through enhanced search engine positioning.

8. Give gifts subscribers can actually use. Offer an opt-in bonus for joining your subscriber list! Write an ebook or provide a PDF business report, or even hire a programmer to create downloadable or web-based software. But don't limit yourself to offering gifts to opt-ins. Give them out when your readers fill out a survey, provide a testimonial, success story, or a great product idea. Let them know when they can expect the next gift offer. Everyone likes to get something for free! And if you pass out 'goodies' throughout the year, your subscribers will feel truly appreciated − and that's good for business!

9. Ask your subscribers to pass it on. Word of mouth is a powerful viral technique that works great with email marketing. If your subscribers find your content interesting, amusing or informative, they'll probably share it with their friends. This can be a great source of new customers, so make sure to remind them to 'pass it on'.

10. Let others reprint your newsletter as long as the content is not modified. If you're happy to share your content with the universe, then why not! Many webmasters and newsletter publishers are actively looking for high-quality content and, if they reprint your newsletter, you'll get new subscribers, and more traffic and links pointing to your site.

11. Include a 'Sign Up' button in your newsletter. If you're using plain text instead of HTML, be sure to provide a text link to your subscription page. You may feel that this is not required because the subscriber is already on your list, but remember that readers will forward your newsletters to others, or reprint them online. Make it easy for them to subscribe!

12. Add a squeeze page. A squeeze page has one goal − to acquire opt-ins and build your list. Think of it as a mini-sales letter to go along with your subscription or opt-in gift. It should feature a strong headline and a couple of powerful benefits that should make subscribers salivate to sign up! Once created, use a service such as WordTracker to find hundreds of targeted keywords, and promote your offer using pay-per-click advertising from Google, MSN and Yahoo. Now that should make a splash!

13. Include testimonials on your squeeze page. This is crucial. Put one or two strong testimonials from satisfied customers on your squeeze page. This can be in any format, but you may find that multimedia (audio or video) is more 'believable' and inspires more people to action. To further enhance believability, get permission to use actual customer names, locations and/or urls (Don't use 'Bob K, FL'). Add a note inviting others to participate. After all, it's free publicity!

14. Blog religiously. Blogging is a great way to communicate with prospects and potential customers, and creates a nice synergy with your email marketing. Be sure to include your newsletter sign-up form on each page of your blog. You can start a free blog at Blogger or WordPress.

15. Post on other blogs. Post thoughtful comments and information on similar blogs with a link to your squeeze or opt-in pages. Also comment on others' blogs through trackbacks. In most cases, your comments will be posted on their blogs with a link back to your site. This is an easy way to generate new traffic and subscribers, and get your brand out there!