I’ve said in the past that I think that best practices are primarily technical. I don’t believe there is a best frequency or a best time to send mail or a best image to text ratio.

My top 6 best practices every marketer should be doing (and too few are).

1. Send technically correct email. That means finding a developer who understands the various email related RFCs including 5321 and 5322 as well as the MIME standard, HTML standards and encoding standards. Don’t rely solely on your vendor to create a correct email for you.
2. Stop sending mail to non-existent or abandoned email addresses. This means correctly handling addresses that bounce and implementing some sort of data hygiene that’s appropriate for your lists and market segments.
   
3. Use VERP in your mail strings. VERP means each email is tagged with the subscriber, list, and even mailing. Having that data encoded in the headers allows troubleshooting, bounce processing and FBL processing much, much easier.
4. Send only opt-in mail. I know a lot of people argue permission is passé but I don’t believe that is true. ISPs, receivers and filtering companies don’t like it when you send mail without permission.
5. Be up front with recipients how you’re going to use their email address. Don’t hide the opt-in language in your privacy policy.
   
6. Send a welcome message. Introduce yourself, introduce your program, get your message in front of your new subscriber as soon as possible after they subscribed. They’re interested in what you have to offer, get into their inbox ASAP to engage them before they move on.
   

How you implement these practices depends on your particular infrastructure, goals and recipient base. Mailers should, though, have appropriate implementations of practices.

There are a number of things that ISPs are monitoring besides complaint rates, although they are being cautious about revealing what and how they are measuring things. I expect that ISPs are measuring things like:

• How many users read a particular mail?
• How many users click through on a particular mail?
• How many users have the senders from: address in their address book?
• How many users receiving the mail have abandoned their accounts or not logged in for months?
• How many users never open a particular mail?

Some of these values senders can measure as well. Senders know, for instance, how many users click through on a mail. They know that some people do open the mail, and they know that some people don’t open the mail. The numbers on opens are not always completely accurate, as to measure opens the recipient must load HTML images. But images are not rendered by default in a number of email clients, and some ISPs don’t show images unless the recipient agrees, or the sender is in the recipient’s address book or the sender is certified by a 3rd party.

Senders don’t have any way of knowing, however, if an email account has been abandoned. That’s something that only the ISPs know. Because of the tools that senders have, there is no difference between an account that doesn’t load images and doesn’t click on any links and one that has been abandoned. Both of these cases will hurt a sender’s reputation, but the abandoned account will hurt more. The ISP figures that if you’re sending mail for months and months to recipients who don’t even log in, that you’re not engaging readers and sending mail recipients want.

What can senders do?

• Senders with websites requiring a login can disable email to that user. The users account can be  and notify users that they will need to resubscribe to the email list when the user next logs in at the site.
• Senders that do not have registration can send re-engagement campaigns to recipients who have not clicked or opened a mail. Users that do not interact with the mail are dropped from the list.

Yes, you will lose names off your list. But those are people who aren’t interested enough in your mail to read it or click on anything for months and months. What value is that name bringing to your business? Does that value outweigh the reputation hit that continuing to mail non-responsive addresses brings?

What happens when marketers fail to be able to suppress email addresses? At some point they’re going to mail someone who gets annoyed enough with them to make it public that they are too incompetent to run an email program.

This happened to the folks over at spamfighter.com recently. They have been spamming Neil Schwartzman (spamfighter, Executive director of CAUCE North America, Director of Standards and Certification at ReturnPath) since somewhere in 2007. Yes, really, 2007. Neil has asked them politely to stop spamming him. He’s explained he’s not actually using their software. They appear to be incapable of running a suppression list, despite telling him 3 times that they have removed his address.

Showing much more restraint than I would have with a sender who couldn’t stop sending me email, Neil gave them years to fix their process before blogging about his experiences. Instead of fixing their broken process they instead responded to his blog post insisting their mail wasn’t spam because they weren’t sending Viagra mail or 3rd party offers.

We can argue about the definition of opt-in, we can argue about whether registration is permission, we can argue about a lot of things, but when the recipients says “stop sending me email” and a sender says “we’ll stop sending you email” and then fails to actually stop sending email I think the recipient is fully justified in calling the email spam. Sorry spamfighter.com, your process is broken and your inability to fix it 2 years after the brokenness was brought to your attention does not give anyone a good impression.

Every email sender should have the ability to stop sending mail to recipients. If that’s not currently possible with your technology, it should be a very high development priority.