A Business Actor can be equated to the external people or systems that interact with the system under study. Actors are not necessarily external to the business; they may also represent internal “user” interactions with the system. Business Actors are high-level conceptualizations of the Actors with the system; further analysis is required to fully understand and define required actors. Note that actors are not individuals nor are they necessarily equivalent to job titles; instead, they describe the behavior in the enterprise and the responsibilities of the associated “user”.

Actors are a categorization, based upon required interactions, of external interactions with the system. At the business level they represent the external entities that interact with the system, be they users or other systems. 

In addition to IT Architects, the following people are interested in actors:

• Business analysts, when defining the boundaries of the organization and required processes;
• Business designers, when describing business processes and their interaction with external entities;
• User-interface designers, as input to capturing characteristics on human [system] actors;
• System analysts, as input to finding [system] actors;