Library Creating better acceptance criteria for user stories Acceptance criteria (ACs) are a key part of user stories. They set the boundaries of what should be achieved - telling the developer when to stop, the QA how to test, and the product owner what to expect. Because they’re used by technical and non-technical people, ACs must use simple language and be non-implementation specific. This post looks at why we changed our approach to ACs on GOV.UK Verify and the effect it has had on the team.