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.