Assumption Log
An assumption log is a project document used to record all assumptions and constraints identified throughout the project lifecycle.
Explanation
Assumptions are factors considered to be true, real, or certain without proof or demonstration. Constraints are limitations or restrictions that affect project execution. The assumption log captures both, providing a centralized reference that the project team can monitor and validate throughout the project.
The assumption log is first created during the Develop Project Charter process, where high-level strategic and operational assumptions are documented. As the project progresses through planning and execution, new assumptions and constraints are added. Each entry typically includes a description of the assumption or constraint, the basis for it, the potential impact if it proves incorrect, the responsible person, and the current status (open, validated, or invalidated).
Regularly reviewing and validating assumptions is essential to proactive risk management. An assumption that turns out to be false can become a risk or an issue. For example, if a team assumes a vendor will deliver components by a certain date and that assumption proves incorrect, the project schedule may be impacted. By tracking assumptions in the log and linking them to the risk register, the project manager ensures that potential problems are identified early.
Key Points
- •Records all assumptions and constraints throughout the project
- •First created during Develop Project Charter and updated continuously
- •Invalid assumptions can become risks or issues — must be monitored regularly
- •Each entry includes description, basis, impact, owner, and status
Exam Tip
Assumptions are things believed to be true but not proven. Constraints are known limitations. Both go in the assumption log. An invalidated assumption often becomes a risk — this is a common exam scenario.
Frequently Asked Questions
Related Topics
Risk Register
The risk register is a project document that records the details of individual project risks, including their identification, analysis results, response plans, and current status.
Issue Log
An issue log is a project document used to record and monitor all issues — problems, gaps, inconsistencies, or conflicts — that arise during the project and require resolution.
Develop Project Charter
Develop Project Charter is the process of creating the document that formally authorizes a project or phase and documents the initial requirements that satisfy stakeholder needs and expectations.
Project Management Plan
The project management plan is the document that describes how the project will be executed, monitored and controlled, and closed.
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