ABAC (Attribute-Based Access Control) in Fauna offers a more flexible and comprehensive approach to access control compared to RBAC, capable of handling complex, dynamic environments by leveraging a wide range of attributes. ABAC uses roles as just one of the many attributes it uses for access control, making it a superset of RBAC regarding capability. It enables real-time evaluation of dynamic information such as data values in documents and time without requiring extensive coding in applications or middleware. This allows for more precise control over who can access what, when, and under what conditions, making it suitable for environments with changing requirements. ABAC can be used to implement complex scenarios that would be difficult or cumbersome to manage in a purely role-based model.