Marketers often equate a successful email marketing campaign with growing email lists. Though having a large list is helpful, you need to engage in relevant communication with your audience. If not, forget conversion - your target audience will not even give your email a second glance. By segmenting your email list and targeting your customers with relevant content based on your segmentation you are sure to reach your audience and give them the feel you know them well. Here are a few ways to segment your email list:

• Geographic Segmentation: By segmenting based on the geographic location of your customer, you get to influence their purchase decisions for locally available products and services. You can attract them to a restaurant with special menus and free drinks and even direct them to a local boutique or offer services peculiar to a particular area.
• Behavior Based Segmentation: An existing customer and a new customer deserve different treatment from the marketer. Since you know what might interest your existing customer by his past purchase behavior, your emails can carry messages referring to those. But you have to tread carefully while assessing a customer who is visiting your website for the first time. Try to learn from their browsing behavior and target them.
• Content Based Segmentation: Study your audience well. Take a look at the content they have browsed on and the product information or marketing offer they have clicked on. You can segment your audience based on this and send lead nurturing emails.
• Loyalty Based Segmentation: Customer loyalty has to be thoroughly appreciated. You can segment based on customers who are frequent buyers, customers who recommended you to others, or non-customers who shared your marketing offers. 

Segmenting your database helps you to send relevant information to your audience that has a higher chance of turning into a sale. Segmentation is an area we are very familiar with at Delivra. We can help you craft emails based on efficient segmentation.

http://blog.hubspot.com/blog/tabid/6307/bid/30240/5-Savvy-Ways-to-Segment-Your-Marketing-Emails.aspx