The boundaries of an information system are determined by identifying which processes, functions, data, and components are under the system's control, and which belong to the external environment. The system includes everything that is implemented and managed internally (for example, modules, databases, internal users), while everything that interacts with it from outside (other systems, external users, regulators) is considered the external environment. For example, for a corporate CRM, the system would include its services and internal data, while the external environment would be mail services or an accounting system with which the CRM is integrated.