Behaviour-Driven Development

A software development methodology that extends Test-Driven Development by writing test cases as human-readable scenarios in natural language, describing expected system behaviour from the user's perspective. BDD test scenarios typically follow a Given-When-Then format that non-technical stakeholders can understand. In accessibility work, BDD is valuable because test scenarios can describe assistive technology user interactions in plain language — for example, "Given I am on the homepage, When I tab navigate to the Search element, Then I should see the search field focused" — making accessibility requirements visible and verifiable across multidisciplinary teams including developers, designers, and accessibility specialists.