>..."Consultants are people who charge you a fortune for interviewing you about your organization and then writing a report repeating what you've just told them and what you already knew!"
Realistically speaking, though, this is actually a very useful thing: providing political cover so that an executive can institute an unpopular but needed change. However, this is more indicative of a weakness in an organization's (perhaps unavoidable in all large companies) culture than it is the effectiveness of consultants.
It reminds me of Richard Feynmann's role in the post-Challenger disaster investigation. He's famously known for explaining the O-ring deficiencies during a televised press conference. But he admits in his memoir that the O-ring revelation was passed to him (through another intermediary), from an anonymous source -- most likely from an astronaut who worried about his/her job -- who had said that the O-ring problem was known to NASA's engineers but the bureaucratic managers had chosen to ignore it.
If all it took was a $1,000,000 fee to get in some consulting engineers (or hell, just Dick Feynmann) to spotlight this fixable -- if inconvenient problem -- so that the Challenger wouldn't blow up, I'm sure we'd all agree that would be money well worth spent.
I know people who go to fortune tellers even though they wouldn't put money on their predictions. But most fortune tellers at least can act as the friendly voice who tells their client want he/she needs to hear, whether it has absolute truth or not.
Has anyone here ever been the beneficiary of a concrete effect from a consultant's work, such as a tangible new idea that resulted in better profits/efficiencies, beyond what is merely CYA?