In any system architecture, a multi-tiered testing strategy is critical. Much of this work is typically behind the scenes in development teams, often following TDD-oriented practices. In agile terms, stakeholders and product owners often never see or grasp what’s being tested. Within the unit testing and integration testing tiers, this tends to make sense. However Behavioral Driven Development (aka Acceptance Test Driven Development) begins with acceptance criteria definition and finishes with the acceptance of a story, providing engagement for all members of an agile team from start to finish.