Hospital Management System ER diagram models five core entities—Patient, Doctor, Appointment, Department, and Room—with their attributes and relationships. Patients schedule appointments with doctors, who belong to departments and handle patient care, while appointments are assigned to available rooms within departments. This normalized schema eliminates data redundancy, enforces referential integrity through primary and foreign keys, and supports mandatory and optional relationships critical for operational healthcare workflows. Fork this diagram on Diagrams.so to customize entity attributes, add new tables like billing or medical records, or export as .drawio for integration into your database design documentation. The legend clearly distinguishes primary keys, foreign keys, and relationship cardinality, making it ideal for onboarding new database administrators or presenting to stakeholders.