How long should it take to write/update a nonprofit case statement?

It can take as long as you want it to. My organization just spent more than two years writing a one-sentence mission statement. Consider writing your case statement over the next three days, without consulting anyone. Show it to a couple of level-headed colleagues and get their ideas. If it's necessary to get others to buy in via some participatory ritual, simply maim several sentences of your statement and give them the opportunity to offer corrections.

Consider writing your case statement over the next three days, without consulting anyone. Do not consider this. First of all, three days isn't long enough to write a case statement even if it wasn't important to get stakeholder input. Second of all, it's important to get stakeholder input. Yes, the process can go on too long to be effective, but it can also be too abbreviated to be effective. If it's necessary to get others to buy in via some participatory ritual, simply maim several sentences of your statement and give them the opportunity to offer corrections. gum, I'm thinking that you don't know what a non-profit case statement is. It's a comprehensive source of information for potential funders. Getting input from stakeholders isn't a "participatory ritual," it's an essential part of the process. This is a multi-page, very detailed document, not a mission statement or a vision statement.

There's no single answer, since it depends on the size of the non profit, the type of programming they do, and how complex their structure is. But I would say that the most important thing to consider in figuring out how long it will take is how well developed and clear the existing mission, vision, etc. are and how consistent those are with what is actually happening on the ground. The points where there are inconsistencies, vagueness or organizational disagreement are those points at which you will get stuck in the stakeholder discussion and the feedback process. The more points of contention, the more frustrating the exercise, and the more likely it is that you will either become completely stuck or end up with a finished product that doesn't meet the needs of the organization. Regardless, done properly it is a significant task. The last two organizations I worked with that went through this process spent hours and hours - the easier, more straight-forward of the two probably rang in around 100 hours plus staff time for input sessions. The more difficult took consultants and senior staff several hundred hours and more rounds of revisions than we ever thought possible, topped off with a document that only about half of the staff were comfortable using. Not to make it sound hopeless - in the latter case there were some serious organizational issues.