GLUE Discipline Design. Enterprise IT Architecture covers all EITA Activities and Deliveries in the context of IT:
While Enterprise Architecture must include Enterprise IT Architecture, but shall not be limited to it, because Enterprise Architects have to look at everything in a holistic way not biased towards anything.
Reality of course is often different and therefore difficult. Enterprise report in most cases direct (or via management structures) to the CIO or CTO. On top of that there is the demand of typical Enterprise IT Architects to be seen as holistic Enterprise Architects spanning the whole Enterprise. And that is a difficult concept for the audience to understand, because of the reporting structure.
What I do not understand though is: What are Enterprise Architects waiting for? If you are hired as Enterprise IT Architect and have something to add to the whole Enterprise Architecture, why don't you just provide it then? Use hte EITA recruiting as the entry to provide the true value. So far I am still waiting for a company to turn that knowledge down. It is usually unexpected, but nevertheless pretty much needed, and therefore also very willingly accepted and used. Asking for governance or an official mandate is calling for trouble if you ask me, because in typical organisations there is no real place for real holistic Enterprise Architects.
The closest could be reporting to the CEO, but everyone is seeking for a position close to CEO. So what is the unified selling proposition Enterprise Architects can make to the CEO compared to all the others who want air time? So any other C-Level reporting structure will normally have to do the trick. That will lead to a somewhat biased situation (the C-Level to report to is the one who drives the potential on how to use and evolve the role).
But if we truly believe in Enterprise Architecture to be a fully holistic non biased function (difficult concept at the moment in time when human beings are involved) then why not just give it a try? Just offer that holistic service to the audience at hand. Provide the knowledge and utilize the existing structures as much as needed, but apply the concepts of the Enterprise Architecture Matrix. And the most important one is, if you believe in being a holistic Enterprise Architect:
Don't think you are, know you are!