Over the previous few chapters, you’ve seen how the BDD life cycle takes acceptance criteria and turns them into executable specifications. Acceptance criteria start as brief notes you write on the back of your story cards that help define when a story or feature is complete. During Three Amigos sessions or other requirements discovery workshops, these notes are fleshed out into more complete examples and counterexamples that illustrate business rules and objectives. And as we saw in the previous chapter, you can write more complete versions of these acceptance criteria in the form of Gherkin scenarios, using the Given ... When ... Then notation.1