Definition of Done vs. Acceptance Criteria

Let's clear up a very common confusion: What's the difference between "Acceptance Criteria" and the Definition of Done, and which is which?

Sometimes, people ask "what is the Definition of Done for this User Story?"
And then, they proceed to document a feature's Acceptance Criteria like this:

1. Feature works
2. All tests passed
3. Documentation written

To make it short: in this example, AC's and DoD are backwards. Now, let's clarify.

Acceptance Criteria

A backlog item's Acceptance Criteria are stated from the perspective of the item's consumer: what defines, for them, that the item is successful?

I hesitate to say, "user acceptance", because sometimes, backlog items are not intended for the end user. If we ignore that case, though, the Acceptance Criteria could be written like simplified User Acceptance Tests: verifiable statements that can be answered with "yes" or "no", and tested by examining the product itself.

Good Acceptance Criteria would be, for example:

• I get informed about my current balance
• I get a warning when my balance is negative
• I get a notification when my balance has changed

As you see, Acceptance Criteria are things that the product does when the item is completed. They are not things that the development team does to the product.

Definition of Done

The Definition of Done is, as the term says, a definition, of what everyone in the development organization, the Product Owner, as well as stakeholders, should understand, when someone uses the term, "Done." 

The Definition of Done is a set of mandatory activities that apply to every single backlog item. It's a checklist-style itemization of things that the team does to the product in order to call a single backlog item "Done."

An example of a Definition of Done is,

• Code written
• All tests Passed
• Successful deployment to Test environment
• Mandatory documentation completed

When you have such a definition, it does not make sense to add these points again to every single backlog item.

But ... the DoD doesn't apply to this item!

Well, it's entirely feasible that the amount of effort to complete a specific DoD activity on an item is Zero. That means it's by default "Done", because all the work required is completed with zero work.

Another thing is when you specifically want to make an exception from your DoD for a specific item. Well, as long as it's an exception, you understand and accept the consequences, and everyone including the customers agrees to take this route, that's okay, because transparency is there.

Although I would caution that if it happens too often, you may want to check whether your DoD makes sense.

But ... it's a specific task for this item!

That's okay. Then add it that task to the item. It's still not an Acceptance Criterion, and it doesn't affect the applicability of the overall Definition of Done.

Discerning: AC or DoD?

	Acceptance Criteria	Definition of Done
Describes ...	What the product does	What the team does
Quality of ...	Product from user perspective	Work from process perspective
Applies to ...	Specifically this backlog item	Generally all backlog items
Met when ...	Verified by a test	Agreed inside team