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Definition of "Requirement"

Here is my definition of "requirement":

"A requirement specifies the least stringent condition that must hold to solve or avoid a prospect problem (problem that a prospective customer faces)."

Note that a requirement, under this definition:
  1. Is possible, in principle, to test.
  2. Does not specify a design or solution.
  3. Correlates unambiguously to a problem that a prospective customer faces.
UPDATE: You can find a comprehensive model of requirements concepts here.

Comments

Unknown said…
Agreed. A good requirement is a statement of the problem, that can be solved, and absent a design of how to solve it.

See my article "On Reqs and Specs" for more. http://www.pragmaticmarketing.com/publications/topics/09/on-reqs-and-specs/
Mon Mar 14, 11:13:00 AM 2011
Lisa Crymes said…
We make this so complicated and yet it's simple. Thanks for the post.
Sat Oct 19, 08:42:00 AM 2013
Cait said…
I love the simplicity of this. Sometimes simplicity is the most difficult to achieve!
Mon Nov 11, 08:58:00 AM 2013
Roger L. Cauvin said…
Thanks, Lisa and Cait. As Steve implied, product managers need to define the problem. The requirements simply specify the conditions that indicate the absence of the problem. Doing so - and not encroaching further into design - empowers designers to unleash their talents and creativity on crafting solutions.
Mon Nov 11, 02:21:00 PM 2013
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