To ensure report scalability, Power BI development should use a modular approach in their report design, allowing for easy updates as the dataset grows. Implementing star or snowflake schemas helps manage large data models effectively. Limit the use of complex calculations and aggregate data whenever possible. Choosing Power BI Premium provides the additional capacity needed for scaling. Implement role-based access control and security protocols to handle increasing user bases. Monitor report performance regularly and continuously optimize both data models and visuals as the size and complexity of the data evolve.