Enterprise Architecture Has Four Domains. The Agentic Enterprise Needs a Fifth.

Four Domains, Thirty Years

And when your architecture review board asks which domain it belongs to, there is no honest answer.

Enterprise architecture has four domains. Business. Data. Application. Technology. Security runs across all of them. For thirty years, that model held, because everything we built was a system the enterprise owned, configured, and ran.

An agent is not a system you run. It is an actor you delegate to.

The Frameworks Describe What You Build

That distinction breaks the frameworks. TOGAF, Zachman, SABSA, FEAF — every one of them describes what the enterprise builds. None describes a non-human actor that holds delegated authority, acts autonomously, and reaches for tools it was never explicitly granted.

We have spent three decades modeling applications. We have no domain for a workforce.

A Workforce With No Org Chart

The enterprise has hired a workforce it never put on an org chart — and no framework tells it where that workforce lives.

The Fifth Domain

That gap has a name: Enterprise Agent Architecture. A fifth domain, alongside the other four, for the agent workforce itself. It has four layers:

• The workforce — which agents exist, what authority they hold, how it is delegated and revoked.

• Capability — what they are permitted to touch, enforced rather than assumed.

• The control plane — where policy meets runtime: the moment an action is allowed, denied, or held.

• Governance — who owns the agents, who audits them, and who is accountable for decisions a human did not make.

Not a Security Problem, Not an Integration Problem

This is not a security problem you can hand to the CISO, or an integration problem you can hand to the platform team. It crosses both, which is precisely why it is an architecture problem.

An Attempt to Be Early

The frameworks will catch up. They always do — late, after the enterprise has already absorbed the shift in pieces and paid for the gaps. This is an attempt to be early.

Enterprise architecture has four domains. The agentic enterprise needs a fifth. Over the coming pieces, I’ll draw it, domain by domain — starting with why TOGAF cannot model a workforce that isn’t human.

The Bridge to Part 1

About This Series

Cite the Position Paper

@misc{saleme2026eaa,
  author    = {Saleme, Michael K.},
  title     = {Enterprise Agent Architecture: The Case for a Fifth Architecture Domain for the Agentic Enterprise},
  year      = {2026},
  publisher = {Zenodo},
  doi       = {10.5281/zenodo.21105314},
  url       = {https://doi.org/10.5281/zenodo.21105314}
}