The Architectural Decision document is composed of four parts. The outline of the document is:
1. Architectural Decision
Describe the Architectural Decision (AD). It is important to briefly state the context and scope of the
Architectural Decision. Use any figures or diagram to help the reader understanding the decision. The reader of this
document should understand the decision and its scope from this summary. This is usually the last section to be
completed when producing and AD.
2 . Impacts and Implications
Document any implications of the decision, such as technology choice, cost, and support implications. Also document and
cross-reference any implications on other ADs, past or present. Things such as:
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How will this Architectural Decision will be applied over time?
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How will this Architectural Decision will be applied in multiple systems?
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What are the skills requirements to support this Architectural Decision?
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Have all stakeholders been involved in that Architectural Decision?
3. Problem & Constraints
3.1 Problem
Describe, in as much detail as possible the problem that this architectural decision will help solve.
3.2 Context
Describe, in as much detail as possible the context of this architectural decision.
3.3 Scope
Define the scope of the problem and the stakeholders.
3.4 Constraints
Describe, in as much detail as possible, the constraints that this architectural decision needs to address. State
any constraints that will limit the options available in solving the problem, things such as:
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Project constraints
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Cost constraints
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Technology constraints
3.5 Assumptions
State any assumptions that will either help in defining the scope of the AD and help in defining and assessing
options, things such as:
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Existing technology givens
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Existing data formats, interfaces, systems and processes that are involved
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Service Level Agreements
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Existing Skills
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Etc.
4. Solution Analysis
4.1. Solution Architecture
Describe the solution to the stated problem in terms of its architecture: how it solves the problem, diagrams, etc.
4.2. Solutions Comparative Analysis
Describe the alternatives that were considered and compare them in terms of meeting requirements,
technologies, cost of ownership, skills requirements, etc..
4.3. Rationale
Explain the rationale behind this Architectural Decision. We often see references to the constraints section in the
justification. If several options were considered, give a brief explanation for the options and list the pros and
cons for each of them—that is provide enough information to support the option chosen and the elimination of the
alternatives. If only one option has been evaluated, then the reason why other alternatives were not considered
needs to be detailed.
Explain how the constraints were considered for this specific Architectural Decision. A well-founded rationale
always helps with the implementation of an Architectural Decision (and its review down the road).
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