What is the Definition of Done?
The Scrum Guide defines the definition of done as follows:
“When a product backlog item or an increment is described as ‘done’, everyone must understand what ‘done’ means. Although this varies significantly per Scrum Team, members must have a shared understanding of what it means for work to be complete, to ensure transparency. This is the definition of ‘done’ for the Scrum Team and is used to assess when work is complete on the product increment.”
The same definition guides the development team in knowing how many product backlog items it can select during sprint planning. The purpose of each sprint is to deliver increments of potentially releasable functionality. These must also adhere to the Scrum Team’s current definition of “done”. Development Teams deliver an increment of product functionality every sprint. This increment is useable, so a product owner may choose to immediately release it. If the definition of "done" for an increment is:
part of the conventions, standards or guidelines of the development organization, all Scrum Teams must follow it as a minimum;
not a convention of the development organisation, the Development Team must define a definition of “done” appropriate for the product.
If there are multiple Scrum Teams working on the system or product release, the development teams on all of the Scrum Teams must mutually define the definition of “done”. Each increment is additive to all prior increments. They should be thoroughly tested, ensuring that all increments work together.
As Scrum Teams mature, it is expected that their definitions of “done” will expand to include more stringent criteria for higher quality. Any one product or system should have a definition of “done” applied to it.
It is worth noting that acceptance criteria are different from the definition of done. A product backlog item’s acceptance criteria serve to remove ambiguity when describing a particular piece of functionality. The definition of done is more technical and all product backlog items should meet the definition of done criteria before they can be considered “done”.