This Part defines the fundamental concepts of Agile Architecture and describes the O-AA approach, the dual Digital and Agile Transformation, architecture development, intentional architecture, continuous architectural refactoring, architecting the Agile Transformation, and Agile governance. A set of axioms for the practice of Agile Architecture is listed in the last chapter.

Enterprises are at various stages of the adoption of Agile methodologies. Figure 1 represents a basic Agile Maturity Model that should help the reader to make an assessment of where they are, and ideally helps to frame the key concepts that follow.