Since the infancy of direct response marketing, a targeted, captive audience has been the key to success.  It didn’t take long for the “list” to become king.

While your list may remain the most powerful pillar of your direct response effort, naturally you also need strong, motivating offers and spot-on creative to go with it.  Still, without the ability to reach the right people, the most enticing offers and the most exceptional creative takes you nowhere.

In online marketing, when it comes to lists the email marketing list reigns supreme .  Still, for most email marketers, achieving continual email list growth is the Achilles heel of email marketing.  This coin of a dilemma has two sides, neither of which is pretty:

Prospect Lists:   You have to constantly replenish the pipeline.  For every sign-up you get there’s a potential unsubscribe. Most email lists are in constant motion – people coming and going all the time.  You can’t assume that every subscriber is going to stick around indefinitely, nor that every prospect will become a customer.  Yet without enough volume of new list members, you won’t have enough prospects to become customers.  So how do you keep the influx flowing, and greater than the out-flow?

Customer Lists:  100% email address coverage on customer lists seems impossible.  Unless you’re a pure-play online business for which email address is required on every sale, some customers are just never going to hand over their closely guarded email address (or the specific address you want).  Others now prefer to communicate with you on social media (largely Facebook and Twitter).  Still more are happy to stay old school – they want phone and direct mail communication.  Send ‘em their catalogs and coupons and they’re content.

So, how DO you entice newcomers to join your list, and then convince those eventual customers who haven’t yet handed over the email address to finally give it up?   In part 1 of this series, I’ll share prospect list growth tactics, then move on to customer list growth strategies in part 2, and wrap it all up with list engagement essentials in part 3.

For now, here are three immediate ways you can attract new prospects to your list:

1. Content Marketing

Want newcomers to join your list? Entice them with worthwhile content they can only get by subscribing – for free of course.  Share insight, knowledge, news or exclusive information in exchange for the email address; and the more exclusive, the better.  Content marketing is the lead generation strategy behind countless webinars, teleclasses, free seminars and white paper offers (mine included).  It’s also the business model behind ad-revenue driven web sites and blogs, on which content is only accessible for free if you’re a registered user.

The challenge?  You’ll need to produce content or already be in a content-driven business to fully leverage this approach.  For those of us who aren’t publishers or media companies, that means intentionally creating content in the form of a blog, video, webinars, audio, teleclasses, information products, e-books, articles and disseminating it (or links to it) as far and wide online as we can.  Yep, it’s work, but it’s an investment in your business and there’s no getting around in the content-hungry Web 3.0 world.  The more distributed content you have online, the more ways people can connect back to your hub – your business’ Web site or storefront.

And, the great news is once you have a content repository, you have a treasure trove of gems you can scatter around step 2:

2. Social Media Presence & Promotion

Still don’t have a Twitter account or Facebook page?  Never checked out Bebo, MySpace, LinkedIn, Digg or even joined a Yahoo group?  Either you’re living in a cave (unlikely if you’re reading this) or mistakenly believing you can get by without these additional online points of presence.

Here’s the reality: social media isn’t a flash in the pan; it’s the new connective tissue of the Internet.   Exactly which sites and communities will survive – and thrive – longterm is still uncertain, but with upwards of 325 million Facebook users you can be pretty sure Facebook isn’t going anywhere soon.

The beauty of participating in social media sites is they give you additional avenues for reaching your target audience, and naturally, inviting them to join your email list.  Social media sites reach demographics and groups you otherwise won’t cross paths with elsewhere online.  So get your social media site pages and accounts set up, then start inviting and enticing friends, followers and connections to the wonderful content you’ve developed (or are launching) in step #1.

3. Joint Ventures and Affiliates

There’s strength in numbers.  A key to reaching more of your target audience is to find out where they’re already hanging out – which on social media you will naturally see and do in step 2 above.  However, they might be hanging out on other people’s email lists, which can be a good thing if your products or services are complementary.

Struggling with content development?  Partner up with a complementary company or specialist to jointly create a new program, product, publication, event, training or even contest.  If you can identify a complementary partner who already has a large email list targeted to your ideal audience, you can offer to do much of the program development in exchange for exposure to their list.  Or, your arrangement can be reciprocal.

Affiliate relationships are also great for list growth, although new rules as of last year require that affiliate relationships now be disclosed up front whether in email list broadcasts or even product reviews on blogs (as an example, Chris Brogan does this really well). Normally, affiliates receive a commission on sales resulting from leads they’ve directed to your sign-up or buy pages which result in sales, so you’ll need an affiliate program management system in order to record referring links and manage commissions, etc. Unlike joint ventures, affiliate relationships can be reciprocal, or not.

As you’re growing your email list, Twitter followers and Facebook fans, keep one major point in mind (it’s not a popular truth, but don’t kill the messenger!).  Totals alone are meaningless.  Once you’ve achieved the growth benchmarks you want, the challenge isn’t quantity, it’s quality. How many of those 11,000 list members are actually opening, reading and engaging with your emails? How many are buying? and how do you keep the momentum going ?   We’ll tackle that in part three of this series, so stay tuned!