I was fortunate to take a course in college on Intelligence and U.S. Policy, taught by a CIA "Officer-in-Residence." (Basically, CIA case officers and analysts who would get two-year appointments as visiting professors... very cool!) Heuer's book was one of our assigned textbooks, and a fascinating read in itself. I was especially influenced by three parts:

-the chapter on the need for analysts to train their minds to understand and process ambiguous information. "We perceive what we expect we will perceive." ... truer words were never spoken.

-the chapter on "do you REALLY need more information;" I was astounded by the finding that while more information may make you more confident that your decision is right, above a certain level more information does not lead to a better decision.

-the process a good analyst goes through when considering differing hypotheses - especially defining possible "diagnostic" future events that would support or falsify the different hypotheses, and looking to disprove hypotheses rather than prove them.

Now I just wish that the CIA would actually take its own advice. Oh well. ;)