According to the PMBOK Guide, 7th edition, section 2.2.1, organizational process assets (OPAs) are the plans, processes, policies, procedures, and knowledge bases specific to and used by the performing organization. OPAs include any artifact, practice, or knowledge from any or all of the organizations involved in the project that can be used to execute or govern the project. OPAs also include historical information and lessons learned from previous projects. Therefore, the project manager's notes should be stored as OPAs, so that they can be accessed and utilized by other project managers in the future. OPAs are inputs to many project management processes and outputs of some project management processes. References:
PMBOK Guide, 7th edition, section 2.2.1, page 37-38
PMBOK Guide, 7th edition
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