During the project lifecycle, an Assumptions Log is required to understand what assumptions have been made in the planning and management of the project. An assumption is a key piece of information upon which project plans and decisions are made. This information has not or cannot be verified and therefore is classified as an assumption and is recorded on the Assumption Log for review throughout the project.
An assumption log is created during project initiation when forming the business case and the content will be used in the project charter. At this stage, high-level assumptions are used. Lower level assumptions based on the tasks and products are created during the project life cycle and the Assumption Log is maintained and reviewed throughout.
Assumptions are made throughout the project in order to be able to proceed with activities, but these assumptions can generate a risk or an issue if the assumption is found to be untrue.
An example of a typical assumption made during a project would be the availability of project resources required to deliver. If the resource is not available for any reason, then the delivery of the project is at risk. This is why the Assumption Log is useful in managing a project as it helps to foresee potential risks and issues that will affect the overall delivery.
Ideally, the Assumption Log will be reviewed regularly and activities should be undertaken to either verify the assumption so it can be closed or alternatively provide a mitigation if the assumption turns out to be incorrect.
Assumptions are prioritised on the Assumption Log in terms of the level of uncertainty and the potential impact to the project if the assumption proves to be incorrect. Assumptions with the highest level of uncertainty and the highest potential impact are treated as the highest priority.
The assumption log should contain the following items for each assumption:
- The date the assumption was first logged
- A category for the assumption, e.g. budget, scheduling, product
- A name and description for the assumption
- A rating for the uncertainty of the assumption (high/medium/low)
- An impact rating for the assumption (high/medium/low)
- An owner for the assumption
- An action plan to mitigate the impact of the assumption should it be untrue
- A date for the next review of the assumption
- A status for the assumption – open or closed