There are four permission levels associated with email marketing that range from loose to rock solid. Depending upon your goals and the amount of risk you're willing to take when it comes to deliverability and blacklisting, the following are your options:

• Opt-out. In the opt-out level of permission, recipients will receive messages unless they actively decline. Examples of opt-out messages include unsolicited email that contains a functioning opt-out link or pre-checked boxes on an order page or preference center that customers must uncheck in order not to receive email marketing messages. The opt-out level of permission assumes approval is granted unless explicit action is taken on the part of the recipient to decline. Although legal under the U.S. CAN-SPAM provisions and commonly used by some companies, it is not considered a best practice among legitimate email marketers. Still, according to MarketingSherpa's Email Marketing Benchmark Guide 2007, 35 percent of BtoB marketers and 21 percent of BtoC email marketers use an opt-out permission process in their email marketing program.
• 
  
• Single Opt-in. Interested parties must actually check a box or click on a link to sign up to receive emails. As the most basic level of permission-based email, the single opt-in is also the most popular. Nearly four out of 10 BtoC email marketers use the single opt-in option and 20 percent of BtoB marketers do, according to MarketingSherpa.
• 
  
• Confirmed Opt-in. In a confirmed opt-in, you not only receive permission, you also follow up with an email message that confirms the person has opted-in. The confirmed opt-in allows you to get explicit permission from a recipient and immediately test your new relationship, creating a good brand impression. Confirmed opt-ins also allow you to verify that the email address you have is valid before it can damage your deliverability. Although this is a best practice, Silverpop has found marketers are lax in implementing such a program. In Silverpop's "2005 Retail Email Marketing Study," only 43 percent of online retailers sent a registration confirmation message.
• 
  
• Double Opt-in. A double opt-in takes the confirmed opt-in one step further by making the recipient confirm and then reaffirm that they did indeed want to receive emails from you. Only after they take this action is the double opt-in considered complete, and only then will your recipient begin to receive information. Less than 7 percent of marketers use double opt-in, according to MarketingSherpa.
  

When evaluating the opt-in process, most marketers need only make a few simple changes to revitalize their list growth efforts. If you're not currently sending confirmation emails, for example, this is a terrific place to start to improve list growth. Additionally, consider these elements of a strong permission-based email marketing program:

• Clearly ask for permission--don't bury the call to action off the home page.
• Provide a good reason for prospects to give you their email addresses by offering relevant topics, programs, messages, etc.
• Give customers choices in content or frequency when possible. A one-size-fits-all mentality fails to achieve the full potential of email marketing.
• Help improve deliverability by sending confirmation messages following registration and requesting addition to recipients’ address books.
  

Based on the level of permission appropriate for your unique business needs, you can implement the right opt-in process to create a list of recipients that are truly interested in your company’s products or services.

Source: SilverPop