In which phase does architecture vision get validated?

The architecture vision is validated during Phase B of the Architecture Development Method (ADM). This phase is primarily focused on the development of the business architecture and serves as a bridge between the architecture vision established in Phase A and the more detailed architecture designs that follow.

During Phase A, the architecture vision is indeed formulated, setting a high-level plan for the enterprise architecture initiative. However, it is in Phase B where this vision is put to the test and aligned with business requirements through detailed analysis. This involves confirming that the architecture vision meets the necessary stakeholder concerns, objectives, and strategic goals, ensuring that it reflects the actual needs of the organization and is feasible within the defined constraints.

Phases C and D shift focus to the data and application architecture and technology architecture, respectively; thus, they are not primarily concerned with validating the architecture vision. Instead, those phases build upon the validated business architecture established in Phase B, composing the subsequent architecture domains within the overall framework.