A subject-matter expert (SME) is a person who is an authority in a particular area or topic.
The term is used when developing materials about a topic (a book, an examination, a manual, etc.), and expertise on the topic is needed by the personnel developing the material. For example, tests are often created by a team of psychometricians and a team of SMEs. The psychometricians understand how to engineer a test while the SMEs understand the actual content of the exam. Books, manuals, and technical documentation are developed by technical writers and instructional designers in conjunctions with SMEs. Technical communicators interview SMEs to extract information and convert it into a form suitable for the audience. SMEs are often required to sign off on the documents or training developed, checking it for technical accuracy. SMEs are also necessary for the development of training materials.
In pharmaceutical and biotechnology areas, ASTM standard E2500 specifies SMEs for various functions in project and process management. In one project, there will be many SMEs who are experts on air, water, utilities, process machines, process, packaging, storage, distribution and supply chain management.
“Subject Matter Experts are defined as those individuals with specific expertise and responsibility in a particular area or field (for example, quality unit, engineering, automation, development, operations). Subject Matter Experts should take the lead role in the verification of manufacturing systems as appropriate within their area of expertise and responsibility.” —ASTM E2500 §6.7.1 and §6.7.2.
In engineering and technical fields, a SME is the one who is an authority in the design concept, calculations and performance of a system or process.
A lawyer in an administrative agency may be designated an SME if he or she specializes in a particular field of law, such as tort, intellectual property rights, etc. A law firm may seek out and use an SME as an expert witness.
In electronic discovery environments, the term “SME” labels professionals with expertise using computer-assisted reviewing technology (CAR) and Technology Assisted Review (TAR) to perform searches designed to produce precisely refined results that identify groups of data as potentially responsive or non-responsive to relevant issues. E-discovery SMEs also typically have experience in constructing the search strings used in the search. It also refers to experts used to “train” the TAR systems.
Wikipedia “Subject Matter Expert” (https://en.wikipedia.org/wiki/Subject-matter_expert)