Have you ever had a person in your project team that understood every single technical detail of the project end-to-end? These are experts. Don't you wish you could have an expert on all your projects? But aren't experts always busy working on the most important projects? To solve this, there is one name in the list of "Tools and Techniques" that you will see over and over again - Expert Judgment Due to its multiple appearances throughout the Project Management landscape and its sheer usefulness, Expert Judgment is often recommended as one of the best tools and techniques. This relies on the very idea that experts are an asset of an organization and should be leveraged in the most effective way possible. Project teams typically need the help of experts during several planning processes. Planning is one of the most important part of Project Management and having an unbiased and expert opinion during planning can help avoid massive goof-ups later. Consider a relatively new project manager working on the project cost estimates. Do you realize the importance of having expert judgment? Same goes with many other processes during the course of project lifecycle from defining scope to identifying risks. Expert Judgment as defined in some books is basically, - Using knowledgeable groups or individuals to assist in project decisions. Who is part of the Expert Judgment Group? Typically someone outside of the project team. It could be one person or a group of people. They could be SMEs, Team Leaders, a separate department within your organization or even external consultants. They will be an expert either in a specific knowledge area, a specific discipline, an industry etc. How is Expert Judgment different from Organizational Process Assets (OPA)? OPA is related to the processes or artifacts. It is also a part of the organization and built on earlier experiences and lessons learned while Expert Judgment could be a group of people totally unrelated to the project.