After a busy February that included a conference focused on reducing email abuse, teaching an “email delivery bootcamp” class at SendGrid, and delivering a few successful onsite delivery consulting sessions with clients, I was reminded that the terminology and overall larger ideas of email and delivery best practices aren’t so easily understood. What really seemed to stick throughout these different engagements was an analogy of how the world of email is closely related to that of a live theater setting. All pieces of an email program, similar to the pieces of a great show, must all be in proper working order to get the best desired result.

So, what’s in front of the curtain?

In Theater: The Stage, Actors

In Email: Subject Line, Message Content

We think of the front of the curtain as the most commonly interacted with portion of email messages. This is a mix of text and images that we see displayed when we view a message. If a message makes it to the inbox, these are the items that entice a user to engage with the sender’s brand. Similar to what is seen on a stage of a play or a show, the content is what gives the reader a full experience. However, the show (just as it is true for email content) is much more easily consumed if all of the necessary functions behind the curtains are taken care of.

So, what’s behind the curtain?

In Theater: The Ropes, Lights, Stagehands, Backdrops
In Email: Authentication, Sending IPs/Domains, HTML Content Domains

For marketers, this is probably the most commonly OVERLOOKED portion of email messages. And, if nothing else is taken from this post, I would hope that it is the importance of what is “behind the curtain” of all email messages.

All email messages have correspondence information located behind the main content that users see. And, this is all shown in the “message header.” A large portion of what is located here are the authentication results. Authentication methods are ways the sender can tell the mailbox provider (aka Gmail, Yahoo) who they are and that their mail can be trusted. The main authentication results most commonly seen are for SPF and DKIM. These are now the default for what mailbox providers expect to see from good senders.

To give a very quick review, these two authentication methods are essentially telling the mailbox provider the following statements (please pay more attention to the statements than the confusing titles that were originally created for each authentication method):

  • SPF (Sender Policy Framework): Hello Mailbox Provider! My sending IP is configured and allowed to send on behalf of my domain and my messages can be trusted.
  • DKIM (Domain Keys Identified Mail): Hello Mailbox Provider! My message content has not been modified in transit and can be trusted as the preserved original content intended for the recipient.

Think of the mailbox provider as a more powerful version of a theater “critic.” The happier they are, the better chance all theater-goers will have at viewing the play favorably (in the email world this translates to having a better chance your mail will get delivered to the inbox).

Just as the audience of a play is only actually seeing the actors on the stage, the play would have a much poorer reception if the lights and backdrop weren’t adding to the overall experience. This holds true for authentication and the infrastructure behind every email message. While the content is what recipients engage with, that presentation has a much better chance at being well received if the mailbox provider is also happy with what is going on behind the scenes.

For more information on all email delivery best practices, feel free to contact our Email Delivery Consultants.



Jacob Hansen
Jacob comes from a background in technical account management and delivery analysis for the last six years, and has been with SendGrid's Deliverability Consultant team for the last two years. He enjoys spreading knowledge to help the email community send more "wanted email" and to help senders realize their full potential. Originally from Nebraska, but living in Colorado long enough for it to feel like home, Jacob enjoys a lot of what the Denver restaurant, bar, brewery and music scenes have to offer.