They ensure that the business, applications, data, and systems are aligned with technology and governance strategies, policies, and standards.
They put plans in place to make sure the overall architecture is maintained in a cohesive manner, and that security and quality concerns are properly addressed.
Furthermore, they help to inform a range of business improvement activities by interpreting, using, and applying information contained within the IT architecture.
Through multiple models, they can show how current and future needs will be met, and help to future-proof the business as much as possible.