The Cockburn Scale is a method for classifying how much ProcessCeremony a project requires based on its criticality and size.  

"Criticality" is defined by the sentence "A defect could cause loss of ":
 
* Life (L)
* Essential money (E)
* Discretionary money (D)
* Comfort (C)

"Size" is defined as the size of the development staff:
* 1-6 (6)
* 7-20 (20)
* 21-40 (40)
* 41-100 (100)
* (extends arbitrarily)

So a two-person, life-critical project is given the rating L6, and a ten-person project that could potentially cause tangible monetary loss but not enough to jeopardize the organization is a D20.

The scale was presented in AlistairCockburn's book AgileSoftwareDevelopment.
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Can we have some concrete examples of the differences between E and D?  From a business case point of view, ''all'' money is essential money.  Depending on some of our customers, the project I am working on now could be classified as either E100 or D100.  Perhaps I'm misinterpreting something? --SamuelFalvo

''The difference is strictly in scale.  If the magnitude of the loss is likely to cause the business to stop functioning, it's "essential".  Otherwise, it's discretionary.  A concrete example: if I run a small business that grosses $1M a year, and the failure would cause a 20% drop in revenue, that hurts a heck of a lot.  On the other hand, if the failure precipitates a $120M liability lawsuit, that's fatal.''
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