Made for intelligence analysts. Now free to the public.
Analysis of Competing Hypotheses is a research technique developed at the CIA over 30 years ago. It was created to help intelligence analysts think clearly and objectively about complex questions involving lots of data points and hypotheses. To learn about it, browse the links to the left under "ACH Basics." If you want the elevator pitch, see Sample Projects. However, if you plan to use ACH for your work, we strongly suggest you read all the contents of the "ACH Basics" heading.
If you're interested in using the software, see that section at left.
Software developers: There's a batch of links for you over there as well.