Why enterprise architecture exists
A board sets three goals and, a month later, there are fourteen projects, several of them building the same thing twice. Enterprise architecture is the work that connects goals to the changes that reach them, so every dollar spent can be traced to a goal. This lesson shows you what that work is, who does it, what it produces, and how it goes wrong.
By the end you can
- Explain the strategy-to-execution gap and spot duplicates, gaps and orphans in a list of proposed projects
- Tell enterprise, business and solution architecture apart by scope and time horizon
- Describe the chain from strategy to capabilities, value streams, applications, technology and a roadmap
- Choose a view by asking which stakeholder needs it and what question it answers
- Name the signs of architecture that fails, and what useful architecture looks like
The everyday picture
Think of a fast-growing city. Each building has its own architect, and a good one designs a building that is safe, useful and beautiful. But no building architect decides where the roads go, where the water pipes run, or which streets are for homes and which for factories. That is the city planner's job.
Without a planner, every building can be excellent and the city still fails. Two hospitals open on the same street while a whole district has none. Each new block digs its own water connection. Traffic jams form because nobody planned the roads to match the new offices. The planner rarely draws a building. The planner keeps a map of the whole city, sets the zoning rules, and decides the order of big works: the water main before the new district, the bridge before the second airport road. In a company, the enterprise architect is the city planner and the solution architect is the building architect. Both are needed, and they work at different scales.
The strategy-to-execution gap
Strategy is a short list of choices. Execution is a long list of projects. Between the two there is a gap, and money falls into it. You met strategy as a kernel of diagnosis, guiding policy and coherent actions. The word that matters here is coherent. When each department turns the goals into its own projects, the actions stop supporting each other.
Here is what usually happens. The board publishes goals. Each department head asks, "What can my team do for this?" Each answer is sensible on its own. Then the answers land on one budget list, and three kinds of problem appear:
- Duplicates. Two projects change the same thing in different ways. Finance and the app team both build credit approvals, so the company ends up with two sets of credit rules that disagree.
- Gaps. A goal needs a change that nobody proposed, because it belongs to no single department. Everyone assumes someone else has it.
- Orphans. Projects that name no goal. Some are pet projects. Others are foundations, such as replacing a system whose support ends next year, that every goal quietly depends on.
Duplicates also create integration spaghetti. Each project connects its new system to whatever it needs, by whatever route is quickest. After a few years nobody can draw how data moves, and every change takes longer than the last.
Mangrove Market is in exactly this position. The board's three-year plan (FY2027 to FY2029) has three goals. G1: double partner-shop revenue, from about $52M a year to about $104M. G2: open in two new cities by mid FY2028, with about 25 stores each, one new distribution centre and about 600 new partner shops. G3: cut the cost to serve a partner order by 30%. Within a month, departments sent 14 proposals worth $4.63M in total. The diagram groups them by what they would change.
Look at the warehouse row. Proposal 5 buys a warehouse management system (WMS) for the new city's DC, $650k. Proposal 6 upgrades North and East from WMS version 7 to version 9, $540k, because the vendor ends support for version 7 in 2027. Read separately, both are fine. Read together, they could leave Mangrove with three WMS setups and three support contracts, unless the new DC joins version 9 too. Look at order capture: proposal 1 adds a rep mode to the Partner app, so sales reps take phone orders in the app; proposal 14 rewrites the 2014 back-office order entry tool for $480k. If rep mode works, the old tool can be switched off. Rewriting it means paying to rebuild something you plan to remove.
Quick check
Proposal 6, the WMS 7 to 9 upgrade, names no board goal. What does that tell you?
Treat an orphan as a question to answer before any verdict. Some orphans are pet projects; others are foundations that the goals depend on without saying so. Tracing it through what it changes (warehouse fulfilment) shows the link. Funding it first by rule skips the same tracing in the other direction.
Enterprise, business and solution architecture
The word architect covers several jobs. Titles vary by company, but three scopes come up everywhere.
Enterprise architecture (EA) looks at the whole organisation, business and technology together, over the same horizon as the strategy, usually three to five years. Its main question is which changes to make, in which order, so the goals are met without building things twice. The TOGAF Standard from The Open Group, the most widely used EA framework, splits this work into four domains: business, data, application and technology.
Business architecture is the business domain of EA. The Business Architecture Guild's BIZBOK Guide describes it as views of the business across capabilities, end-to-end value delivery, information and organisation, and how those connect to strategy, products, policies, initiatives and stakeholders. A business architect can talk about Mangrove's partner business for an hour without naming a system.
Solution architecture designs one change: a product, a feature, a migration. Its horizon is the life of a project, months to a year or two. It answers how to build this one thing well and how it plugs into what exists. You did a lot of this thinking in the system design lessons.
| Enterprise | Business | Solution | |
|---|---|---|---|
| Scope | The whole organisation | The business side of it | One change or product |
| Horizon | 3 to 5 years | 3 to 5 years | Months to 2 years |
| Main question | Which changes, in what order? | What must the business be able to do? | How do we build this well? |
| At Mangrove | The FY2027 to FY2029 plan | How partner credit should work | Rep mode in the Partner app |
The three need each other. The solution architect for rep mode needs to know whether credit checks will live in the ERP finance module or in a new service, and that is an enterprise decision. The enterprise architect needs solution architects to say what a change really costs. A business analyst moving into this work already has the core skills from the Business Analysis course: asking why, separating the problem from the requested solution, and modelling what happens today. Business architecture applies them to the whole business instead of one project.
Quick check
Ken asks which message queue the rep mode service should use to send orders to the ERP. Whose question is that, mainly?
Choosing a queue for one service is a design decision inside one change. The enterprise view matters only as context: if Mangrove has a standard job queue, the solution should use it. Escalating every design choice to the enterprise level is how architecture becomes a bottleneck.
The chain from strategy to roadmap
Enterprise architecture is easier to learn as one chain of questions. Each link answers the question the link above raises, and this course follows the chain lesson by lesson.
- Strategy and goals. What are we trying to achieve, measured how? G1's measure is partner revenue: today about 1,800 shops × 2.2 orders a week × $250 × 52 weeks ≈ $52M; the target is about 2,700 shops × 2.6 orders × $285 × 52 ≈ $104M.
- Capabilities. What must the business be able to do, and do better, to hit those numbers? Adding 900 shops (2,700 minus 1,800) means Mangrove must get much better at partner onboarding, partner order capture and partner credit management. You will map these in ea-02.
- Value streams. Where does value flow and where does it break? A partner order goes from placing it to Mangrove being paid. Shops pay about 23 days after delivery on 14-day terms. That is a break, and ea-03 measures it stage by stage.
- Information and applications. Which systems and data support each capability, and where are they duplicated, missing or unfit? Partner master data lives in three places that disagree on about 1 shop record in 8 (ea-04).
- Technology. What do those applications run on, and what constrains them? Support for WMS version 7 ends in 2027 whatever the board decides.
- Initiatives and roadmap. Which funded steps close the gaps, in which order? This is where the 14 proposals get merged, reshaped and sequenced (ea-05), in the spirit of the outcome roadmaps you already know.
The chain gives you traceability in both directions. Down: for G2, which capabilities, systems and projects must change? Up: for proposal 14, which capability does it improve and which goal does that serve? When the board asks why it should fund $4.63M, the answer is a traced picture instead of fourteen separate business cases.
Think first: why put capabilities between goals and projects, instead of linking each project straight to a goal?
Because projects change and capabilities don't. Linking projects straight to goals is what hid the duplicates: proposals 3 and 4 both linked correctly to a goal (G3 and G1), and nobody saw that both change partner credit management. When every project must name the capability it changes, two projects naming the same capability stand out at once. The capability is the shared key that makes overlaps and gaps visible, the way a city map shows two hospitals on one street.
Views that answer someone's question
What do architects produce? The tempting answer is documents and diagrams. The useful answer is decisions, supported by a few pictures that each answer one person's question.
The international standard for describing architectures, ISO/IEC/IEEE 42010 (latest edition 2022), gives you the words. A stakeholder has concerns, the questions they need answered. A viewpoint is a reusable recipe for one kind of picture: which concerns it covers, for whom, in which notation. A view is the actual picture you make with that recipe for your situation. The standard deliberately does not tell you which views to draw. That depends on who is asking.
| Stakeholder | Their concern | A view that answers it |
|---|---|---|
| The board and CFO | What does each goal cost, and what are we funding that serves none? | Investment by goal, through capabilities |
| Head of partner sales | When can reps stop re-keying phone orders? | Roadmap for order capture, by half-year |
| Head of operations | Which WMS will the new DC run, and when? | Applications on the warehousing capabilities |
| Ken, engineering manager | Which systems change, and what connects to what? | Application and integration view |
| Finance credit team | Where are credit decisions made and recorded? | Credit information and process view |
Two habits follow. First, start every view from a named stakeholder and a question. If you can't name either, don't draw it. Second, keep the views few and alive. Five views that are updated each month and used in real decisions are worth more than fifty in a repository. Gregor Hohpe calls the architect's job riding the "architect elevator": moving between the boardroom and the engine room, and carrying each side's reality to the other. Views are what you carry.
Quick check
The CFO asks "why are we spending $1.19M on warehouse software?" Which response fits the stakeholder?
Her concern is cost and value, so the view links money to goals and shows the choice she can make. An interface diagram answers an engineer's concern. Handing over everything answers nobody's question and pushes your work onto her.
When enterprise architecture fails, and what good looks like
Many people have met EA at its worst, so expect some doubt when you start. The failures are well known:
- The ivory tower. Architects draw target states for a future that delivery teams never see, and the teams build around them.
- Frameworks first. Six months spent tailoring a framework and a model of every element type before answering one real question. Frameworks such as TOGAF say themselves that they should be adapted to the organisation. You will see how to use TOGAF lightly in ea-06.
- The 300-page document. A complete current-state description, out of date the week it is approved, read by nobody.
- Architecture police. A review board that every change must pass, adding weeks, so teams learn to hide their changes.
Good architecture looks smaller and faster. It is judged by decisions: duplicates merged, gaps filled, foundations funded before the work that needs them. It keeps a few living views, such as the capability map, the application map and the roadmap, and updates them as decisions are made. And it gives fast answers. When the head of operations asks which WMS the new DC should run, a good architecture team answers in days, with the trade-offs, because the map already exists.
A simple test for your own work: for each thing you produced last month, name the decision it changed. If the list is empty, you are drifting toward the ivory tower.
Quick check
A new architecture team proposes to spend its first two quarters documenting every Mangrove system before giving any advice. What is the main risk?
The budget round won't wait two quarters. Architecture earns its place by answering the questions being asked now, starting with the systems those questions touch, and growing the map as it goes. Completeness first is the frameworks-first trap in another form.
Do it
Build a goal trace for a list of proposed projects, and turn it into a one-page answer for the person who funds them.
Write the goals with their measures
Take the strategy's goals and add a measure, a baseline and a target to each, as you did for outcome goals in OKRs and outcome goals. A goal with no number can't be traced to.
OutputG1 Partner revenue $52M/yr (1,800 shops x 2.2/wk x $250 x 52) -> $104M/yr (2,700 shops x 2.6/wk x $285 x 52), end FY2029 G2 New cities 0 -> 2 cities, ~50 stores, 1 new DC, ~600 shops, mid FY2028 G3 Cost to serve -30% per partner order, end FY2029List every proposal on one sheet
One line each: owner, cost, the goal it claims, and what it changes. Ask for the proposals that are already under way, too; they compete for the same people.
Markdown| # | Proposal | Owner | Cost | Goal claimed | What it changes | |----|-------------------------------|------------|--------|--------------|--------------------------| | 1 | Rep mode in the Partner app | Sales + IT | $420k | G3 | Partner order capture | | 14 | Rewrite back-office order entry | IT | $480k | none | Partner order capture | | 5 | WMS for the new-city DC | Operations | $650k | G2 | Order fulfilment at DCs | | 6 | WMS 7 to 9 at North and East | IT | $540k | none | Order fulfilment at DCs |Group by what changes, then mark three things
Sort by the last column. Two or more proposals on the same thing are a duplicate to merge. A goal that needs a change no proposal covers is a gap. A proposal with no goal is an orphan to trace. Use rough capability names for now; ea-02 gives you a proper map.
Trace every orphan
For each one, ask what breaks if it doesn't happen, and which goal that hurts. Re-link the foundations, hold the rest, and write the reason next to each.
Write the one-page answer
Name the stakeholder and the question at the top. Answer in their terms, and end with the decisions you need from them.
MarkdownFor: CFO. Question: what does each goal get, and what serves none? Answer: G1 $1.34M, G2 $0.74M, G3 $1.17M, no goal $1.38M (of $4.63M). What the totals hide: - 5 groups of overlapping proposals hold $3.62M; merge them before funding. - G2 has a gap: nobody onboards the ~600 new partner shops. - 2 orphans are foundations (WMS upgrade, partner master data): re-link them. - 1 orphan works against G3's plan (order entry rewrite): hold it. Decisions needed: approve merging; fund a 6-week target-state study.
Bring it to your team
Ask these in the next planning or budget meeting.
- Which goal does this project serve, and through which capability?
- Is anyone else changing the same capability or the same data this year?
- Which goal needs a change that no proposal covers?
- For each project with no goal, what breaks if we don't do it?
- Which decision did our last architecture document change?
Red flags
- Each department submits its own list and nobody reads them side by side.
- Two projects build the same rules, data or integration in different systems.
- Architecture output measured in pages or diagrams instead of decisions.
- End-of-support upgrades funded only after the support has ended.
- A review gate that teams describe as something to get around.
Practice
Spend by goal, including the orphans
The tables hold Mangrove's three goals and the 14 proposals. goal_id is empty (NULL) for proposals that name no goal. Return one row per goal with columns goal (the goal id), initiatives (how many) and total_cost_k (their total cost in thousands of dollars), plus one row with goal = 'none' for the proposals with no goal. The starter uses an inner join; run it and see which money disappears.
CREATE TABLE goal (id text PRIMARY KEY, name text);
INSERT INTO goal VALUES
('G1', 'Double partner-shop revenue'),
('G2', 'Open in two new cities'),
('G3', 'Cut cost to serve a partner order by 30%');
CREATE TABLE initiative (id int PRIMARY KEY, name text, cost_k int, goal_id text REFERENCES goal(id));
INSERT INTO initiative VALUES
(1, 'Rep mode in the Partner app', 420, 'G3'),
(2, 'Partner app checkout redesign', 380, 'G1'),
(3, 'Credit approval workflow tool', 260, 'G3'),
(4, 'Credit limit and requests in the app', 310, 'G1'),
(5, 'WMS for the new-city DC', 650, 'G2'),
(6, 'WMS 7 to 9 upgrade at North and East', 540, NULL),
(7, 'Route planning tool for the new DC', 90, 'G2'),
(8, 'Route planning for North, South, West', 210, 'G3'),
(9, 'Partner master data clean-up', 240, NULL),
(10, 'Sales rep CRM', 300, 'G1'),
(11, 'Mobile wallet payment of invoices', 280, 'G3'),
(12, 'Partner loyalty points', 350, 'G1'),
(13, 'Partner sales dashboard', 120, NULL),
(14, 'Rewrite back-office order entry', 480, NULL);
-- Spend per goal, plus a 'none' row for proposals with no goal
SELECT g.id AS goal,
count(*) AS initiatives,
sum(i.cost_k) AS total_cost_k
FROM initiative i
JOIN goal g ON g.id = i.goal_id
GROUP BY g.id;
[{"goal": "G1", "initiatives": 4, "total_cost_k": 1340}, {"goal": "G2", "initiatives": 2, "total_cost_k": 740}, {"goal": "G3", "initiatives": 4, "total_cost_k": 1170}, {"goal": "none", "initiatives": 4, "total_cost_k": 1380}]
Show a solution
-- LEFT JOIN keeps initiatives with no matching goal;
-- COALESCE gives their NULL goal a readable label.
SELECT coalesce(g.id, 'none') AS goal,
count(*) AS initiatives,
sum(i.cost_k) AS total_cost_k
FROM initiative i
LEFT JOIN goal g ON g.id = i.goal_id
GROUP BY coalesce(g.id, 'none');
-- To list the orphans themselves (an anti-join):
-- SELECT i.id, i.name, i.cost_k FROM initiative i
-- WHERE NOT EXISTS (SELECT 1 FROM goal g WHERE g.id = i.goal_id);The inner join silently drops the four orphans, $1.38M of the $4.63M, which is exactly the money the CFO asked about. If a goal could have no initiatives at all, start from goal or use a FULL JOIN so that goal still appears with a count of 0. In a real model a proposal can serve several goals through several capabilities, so you would use a link table with one row for each initiative and capability it lifts, the overlay you build in Capability maps.
Duplicate, gap or orphan?
Classify each finding and say in one sentence what you would recommend. (a) Proposal 7 buys a route planning tool for the new DC, proposal 8 rolls out route planning to North, South and West, and East already uses a small SaaS tool. (b) G1 needs about 900 more partner shops, and no proposal changes how shops are signed up and checked. (c) Proposal 13, a partner sales dashboard, names no goal. (d) Proposals 3 and 4 both build credit approval rules, one in a finance tool and one in the Partner app.
- You classify (a) and (d) as duplicates, (b) as a gap and (c) as an orphan
- For (a) you recommend choosing one route planning approach for all five DCs, starting from what East already uses
- For (d) you recommend one set of credit rules used by both finance and the app
- For (c) you trace the orphan and notice it depends on partner master data being fixed first
Show a model answer
(a) Duplicate: three route planning approaches across five DCs. Evaluate East's SaaS tool for all five before buying a second one, and merge 7 and 8 into one piece of work. (b) Gap: partner onboarding belongs to no single department, so nobody proposed it; add it under G1 and G2, since the 600 new-city shops are part of the 900. (c) Orphan: a dashboard has some value for G1, but it would report from partner data that disagrees on about 1 shop record in 8, so hold it until the master data clean-up (proposal 9) is done. (d) Duplicate: two credit rule sets would give shops different answers in the app and on the phone. Decide where the rules live once, then have the app and the finance tool both use them.
Check yourself
The head of marketing proposes a $350k partner loyalty programme for G1. It overlaps with nothing else on the list. What is the most useful architecture question to ask before it is funded?
A project with one owner can still depend on shared foundations. Loyalty points need a single, trusted partner record; with three disagreeing copies, points go to the wrong shop. The framework question is the frameworks-first trap, and the language question is a solution-level detail.
Which statement best describes the difference between business architecture and solution architecture?
The difference is scope and horizon. Reporting lines vary by company, and both roles can use either framework or notation. Option C reverses the scopes.
Six months into the plan, a delivery team says "architecture is where projects go to wait". Which change would most likely fix this?
The complaint is about speed, so measure and fix speed while keeping review for the decisions that matter. A longer document is the 300-page trap; reviewing everything makes the wait worse; dropping review entirely brings back the duplicates EA exists to prevent.
Flashcards
Key takeaways
- Goals split into department projects produce duplicates, gaps and orphans; at Mangrove, five overlapping groups hold $3.62M of $4.63M asked for.
- Enterprise architecture plans the whole organisation's change over the strategy's horizon; business architecture is its business side; solution architecture designs one change.
- The chain from goals through capabilities, value streams, applications and technology to a roadmap makes every dollar traceable to a goal.
- Architects produce decisions, supported by a few living views, each answering a named stakeholder's question.
- Trace orphans before cutting them: some are the foundations every goal depends on.
Sources and further reading
- The TOGAF Standard, 10th Edition, The Open Group, 2022
- ISO/IEC/IEEE 42010:2022, Software, systems and enterprise: Architecture description, ISO, 2022
- A Guide to the Business Architecture Body of Knowledge (BIZBOK Guide), Business Architecture Guild
- The Software Architect Elevator, Gregor Hohpe, O'Reilly, 2020
- Who Needs an Architect?, Martin Fowler, IEEE Software, 2003