Assumption Log

You know what they say about assumptions... and no one wants that. Stay ahead of the game, and don’t ever fall behind.

No matter the project, you’re going to need to make some educated guesses. Be sure you log these assumptions as they’re made, and validate them all. If you’re not paying attention, you’ll never know which ones are right – and even more dangerously – which are wrong.

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The Assumption Log is a document which the project manager and team use to capture, document, and track assumptions throughout a project’s lifecycle. Assumptions are an important part of any project. Assumptions usually require some type of follow-up or validation in order to determine whether or not they will impact the project. Many assumptions may actually be project risks, or may become risks during the life of the project. In addition to creating an assumption log, be sure to perform proper risk management on your project with a risk management plan and risk register. The assumption log should be used to augment your risk register - it should never be used in place of the risk register.

Each assumption should have an owner or team member responsible for following up and validating the assumption. The Assumption Log assigns each assumption an ID or reference number, a name and description of each assumption, responsible person, due date, status, closure date, and any actions which might be required as part of the follow-up or validation.

The Assumption Log should be updated as items are closed or more information is obtained. The project team should also review the Assumption Log regularly to ensure all project team members are informed and any additional actions or information is captured.

Standard Assumption Log Template:

Assumption Log
Project: Date:
ID Category Assumption Responsibility Due Date Status Actions
Each assumption should have a corresponding ID number. This should list what portion of the project the assumption impacts. Define the assumption in this column. Assumptions should be assigned to a team member to validate. This is the date the assumption should be validated by. This tracks the assumption validation and if it's open or closed. Any actions associated with the assumption or validating the assumptions should be listed here.

Example with Sample Data:

Assumption Log
Project: Date:
ID Category Assumption Responsibility Due Date Status Actions
001 Manufacturing There is adequate capacity on manufacturing lines to produce prototypes for the project. J. Brown 6/1/20xx Open J. Brown to meet with operations manager on 4/15 to discuss line capacity.
002 Design Cable dimensions will not deviate significantly from existing product lines. P. White 5/15/20xx Open Design team is currently verifying planned cable dimensions.
003 Supply There is adequate warehousing space for additional materials needed for this product. T. Black 5/1/20xx Closed T. Black has verified that there is ample warehousing space available for the Xwave Fiber Project.
004 Planning/ Execution All project resources will remain available throughout the project lifecycle. A. Green 4/15/20xx Open A. Green will meet with Sponsor and all functional managers on 3/13 to discuss this topic.