Library Management System use case diagram maps interactions between three actor roles—Student, Librarian, and Admin—and twelve core system functions. Students perform self-service operations: Search Book, Borrow Book, Return Book, and Register User, while Librarians handle Manage Inventory and Approve Borrow Request workflows. Admins control Manage User Accounts and Configure System settings, establishing clear role-based responsibility boundaries. This use case model documents functional requirements and actor responsibilities, essential for requirements gathering, test planning, and stakeholder alignment before development begins. Fork this diagram on Diagrams.so to customize actor roles, add new use cases like Reserve Book or Fine Management, or export as .drawio/.svg for inclusion in design documentation.