If you have a large list that sends multiple emails a day, it may be desirable to ensure an activist will only get one email a day even if they would be included in more. This can prevent them from getting overwhelmed and unsubscribing from your list. Mailstream allows you to set up a queue of emails from highest to lowest priority, while ensuring activists only receive one email a day.
With Mailstream, you can group emails together for a given day and set their order of priority. When viewing the Mailstream, emails will be listed in order from the broadest audience at the top, to the narrowest at the bottom. Emails at the top of the mailstream will exclude activists receiving any emails listed below them. Emails with the widest audiences should be arranged towards the top. Emails that can go to smaller, more tightly targeted audiences should go further down.
As you arrange your mailstream, you'll need to click the recalculate button on the right side to ensure the emails have been retargeted based on the mailstream you've set up. If you make any changes that require an email to be recalculated, you'll see the recalculate icon appear next to them. Be sure to recalculate from the bottom to the top to ensure emails are targeted correctly and activists only receive one email that day.
As an example, my group is going to send three emails tomorrow: a general newsletter, a request for a donation, and a call to action for a bill being considered in New York City. To ensure people only get one email a day from me, I'd arrange my newsletter at the top (large audience), followed by my donation request (smaller audience), and finishing with my call to action (hyperlocal audience). Someone on my list who lives in New York City and is a donor would only receive the call to action. People who live anywhere else and are donors would get my donation email. People who are not in New York City and aren't donors would receive my newsletter. This allows me to reach everyone I need to that day with relevant content, and not overwhelm them with emails. The email at the top excluded anyone who received emails further down the mailstream that were more tightly targeted to them.
Note: The order of the emails in the Mailstream is not the order in which emails will be sent. They will still follow any scheduling you set up for it. Adding them to the Mailstream allows you to prioritize which email people will receive for that day.
A mailstream can be set up in two places. First, at the bottom of the Emails tab of the Group Manage page. Here, you can search for emails (included past sent and drafts) to include in the Mailstream. Second, in the targeting page for email. On this page, click the red 'Add to Mailstream' link.
To arrange your Mailstream, first select the day you'd like to send the email. Any emails already scheduled to go out that day will be listed here. In the Emails tab of the Group Manage page, you'll see a drop down menu to search for past sent emails, drafts, or scheduled sends. In the targeting page, you'll only see the option to click the red +Add This Email option. After you've added the email to the Mailstream you can use the icon on the left to drag and drop the emails and arrange them in order of priority. Remember to refresh the targeting for your emails starting from the bottom to the top to ensure activists only receive one email that day.