Power BI developers should design scalable solutions by using modular and reusable components such as templates, standardized visuals, and shared datasets. Data models should be optimized for performance from the beginning, ensuring that they can handle growing data volumes. Power BI developer should document processes and best practices for future teams to follow. Scalable solutions often involve setting up incremental refresh and creating a clear hierarchy of data sources that can accommodate future growth. Scalability ensures that Power BI solutions can evolve with the client’s needs without frequent redesigns.