My belief is that effective enterprise architecture, particularly in an agile environment, is:
- Business driven. Minimally your EA effort should be driven by your business, not by your IT department. Better yet it should be business owned, although this can be a challenge in many organizations because business executives usually aren't well versed in EA and view it as an IT function. Yes, IT is clearly an important part of EA but it's not the entirety of EA nor is it the most critical part. In many organizations the IT department initiates EA programs, typically because the business doesn't know to do so, but they should quickly find a way to educate the business in the need to own your organization's EA efforts.
- Evolutionary. Your enterprise architecture should evolve over time, being developed iteratively and introduced incrementally over time. An evolutionary approach enables you act on the concrete feedback that you receive when you try to actually implement it, thereby enabling you to steer its development successfully.
- Collaborative. The EA survey clearly pointed to "people issues" being critical determinants of success, and of failure, of EA programs. My experience is that the best enterprise architects, just like the best application architects, work closely with the intended audience of their work, both on the business side of things as well as on the IT side. They will "roll up their sleeves" and become active members of development teams, often in the role of Architecture Owner on agile teams or Architect on more traditional teams. Their mission is to ensure that the development teams that they work with leverage the EA, to mentor developers in architecture skills, and to identify what works and what doesn't in practice so that they can evolve the EA accordingly. Enterprise architects, architects in general, who don't participate actively on development teams (holding architecture reviews isn't active participation) run the risk of being thought of as "ivory tower" and thus easy to ignore.
- Focused on producing valuable artifacts. The most valuable artifacts are useful to the intended audience, are light weight, and ideally are executable. Many EA programs run aground when the enterprise architects focus on artifacts that they've always wanted but that development teams really aren't very excited about -- yes, it might be interesting to have a comprehensive comparison of cloud technologies versus mainframe technologies, but a collection of reusable services would be fare more interesting to them. A detailed enterprise data model indicating suggested data attributes would be intellectually interesting to develop, but a list of legacy data sources with a high-level description of their contents would be immediately valuable to many development teams. A detailed model depicting desired web services would be useful, but an actual collection of working services that I can reuse now would be even better.
- An explicit part of development. In Disciplined Agile Delivery (DAD) architectural activities are an explicit part of the overall delivery process. Part of the architectural advice is that delivery teams should work closely with their organization's enterprise architects so that they can leverage the common infrastructure, and sometimes to help build it out, effectively. Disciplined agile teams realize that they can benefit greatly by doing so.
The Agile Scaling Model (ASM) calls out addressing enterprise disciplines, such as enterprise architecture, as one of eight scaling factors which may apply to a given project. The interesting thing about this scaling factor is that it's the only one where things get potentially easier for development teams when we move from the simple approach, having a project focus, to the more complex approach, where we have an enterprise focus. By having a common infrastructure to build to, common guidelines to follow, and valuable artifacts to reuse project teams can benefit greatly. So, I guess my advice is to seriously consider adding enterprise disciplines to your agile strategy.