QUESTION: What is a business case?

["Graham, Debra" <dgraham -at- DCN -dot- ATT -dot- COM>]

Hi all!

   I am currently tasked with writing a business case but having never
worked on one, I'm not quite sure what it is supposed to include.
(Actually, someone else started the business case last year but never
finished it, so I'm being asked to update and revise it.) I'm looking
for a good model, references to books about how to write one, tips and
tricks, etc.

I've gone to the public library for information about business cases but
haven't been able to find anything. (Business plans, business
policies--yes.  Business cases--no.)  Is this a genre specific to AT&T
(the company I'm working for) or is it used by other companies?

From what I have to work with, I'd say a business case is:

* a type of proposal
* written to an internal audience
* requesting and justifying the request for funds (in this case, more
hardware to support an internal product)

I found a couple old ones from elsewhere in the organization but they
are somewhat different in the type of information they include.  I'm
using these as models for right now but I'm hoping to find a reference
that will help me to resolve the differences.  Since the business case
is supposed to go to vice-president types, I want to be sure to include
the information they want in the format they want!

Any help you could provide would be greatly appreciated!

Thanks,
Debra Graham
dgraham -at- dcn -dot- att -dot- com