During which phase of TOGAF do stakeholders approve the architecture vision?

The architecture vision is approved during the architecture vision phase in TOGAF. This phase is critical as it sets the foundation for the entire architecture development process. During this phase, stakeholders engage in discussions to refine and finalize the architecture vision, ensuring that it aligns with business goals and addresses the key concerns and constraints of the organization.

By securing stakeholder approval, the architecture vision gains the necessary backing for subsequent phases. This alignment is essential for ensuring that the solutions developed later on are in harmony with the organization's strategic objectives, thereby increasing the likelihood of successful implementation.

Other phases, such as the implementation phase, focus on executing the plans rather than approving initial visions, while the requirements phase is about gathering and managing requirements. The preliminary phase serves to establish the foundational context for the architecture work but is not where the vision approval occurs.