Mission statements clearly have internal organizational value; when they are well written they provide the staff, volunteers, and the board with a very clear organizational purpose. They help make sure everyone is aiming in the same direction, and they help you figure out what to include just as much as they help you exclude. They may even have external value, helping folks outside your organization figure out just what you do.
But it’s a separate question altogether whether to include your mission statement on your home page. Not only are mission statements often vague, they are also often boring, and the last thing you want on your home page is uninspired prose that dulls potential donors or partners into lethargy or, worse, frightens them away.
It seems to me that what matters is whether your visitors can quickly figure out what you are about. If posting your mission statement on your home page gets you there – if it’s tight and clear and inspired – then it might be a good option. But you might find better ways to convey your mission without actually spelling it out. From the rotating images in the center of the page, most of which are about protecting wilderness, to the “Help us protect wilderness” box below that, and the Take Action box about passing four million acres of wilderness just to the right, The Wilderness Society’s home page does an awfully good job of conveying a very simple, clear mission without bothering to rely on an actual mission statement.
But the home page for our friends at the San Juan Citizens Alliance is less clear. The navigation bar is all environmental except, well, for the ones that aren’t, and the content across the home page spans a lot of terrain: air quality, fiscal policy in the state constitution, the Green Business Roundtable. The point isn’t about how they’ve selected the programs on their agenda, but about how effective the home page is at quickly communicating a clear story about what the San Juan Citizens Alliance is and what they do. To be fair, it may be that SJCA’s web site is well-tuned to the audiences they are targeting with their web site (and SJCA has also been one of the best-run nonprofits in Colorado for years), but the comparison draws attention to the value of clearly communicating your organization’s raison d’etre and, even more, to the point that clearly communicating your mission may not involve actually spelling out your mission but evoking and conveying it through a combination, as my KickAssNonprofits.org colleague Ted Fickes says, of design, content, and interaction.