If you get ten nonprofit consultants in a room and ask them how to write a mission statement, you may get ten different answers. Writing a mission statement tends to be more art than science. Which can lead to a lot of frustration.
A mission statement needs to do two things:
Briefly describe what you do.
Briefly describe the group you do it for.
To me, a one-sentence mission statement does this best. The brevity of the statement helps to ensure that the statement will actually get used and not just posted on the wall in a nice frame.
Turns out that lots of others feel the same way. Check out this list of 50, one-sentence nonprofit mission statements.
If you like the one-sentence approach, here is a worksheet that you can use to create your own mission (and vision!). I got this worksheet from the Top Nonprofits website.
All of that said, a one-sentence mission statement doesn't do a good job of describing the depth of an organization. With that in mind, some organizations present their mission statement and then follow it up with additional information. Check out these sites to see what I mean:
Hope this helps you in your mission statement efforts!
(Also, check out this video called How to Write Mission Statements That Don’t Suck. It’s from the author of one of my favorite books!)