As a rule of thumb, domain experts are either the people coming up with requirements or the software’s end users. The software is supposed to solve their problems. The domain experts’ expertise can have different scopes. Some subject matter experts will have a detailed understanding of how the entire business domain operates, while others will specialize in particular subdomains. For example, in an online advertising agency, the domain experts would be campaign managers, media buyers, analysts, and other business stakeholders.
