LinkedIn: How would you define a "business architecture?" And how would you show ROI on developing one?

<question group="Service Oriented Architecture Special Interest Group" >
How would you define a "business architecture?" And how would you show ROI on developing one?
My understanding is that a business architecture is comprised of an enterprise core and supporting processes, business process maps or models for these processes, and how the technology aligns to them.
What else would you add to this definition?

</question>

From my terminology...

business architecture, noun
part of enterprise architecture concentrating on the conceptualisation and evolution of the form and structure of the enterprise business system

Remark: The issues of greatest importance for business architecture are the following:
• core end-to-end business processes (also known as value streams);
• governance structures;
• core business information (semantics);
• communication with core business partners.


enterprise business system, noun
top level view of an enterprise as a system for conducting the business


enterprise architecture, noun
coherent set of proven tools and practices which provides guidance and practical help for the effective transformation of an enterprise to achieve business vision and strategy

Remark 1: Examples of business vision and strategy are: higher level of maturity, greater agility, better collaboration, merging, cost cutting, modernisation of legacy applications, outsourcing the whole unit, etc.

Remark 2: Some parts of enterprise architecture are dedicated to different stakeholders.

Thanks,
AS