Power BI Development Services employ data connectors to seamlessly integrate diverse sources like Excel, SQL Server, Salesforce, and Azure. Developers utilize Power Query to clean, transform, and consolidate data from disparate systems into a unified format. Advanced ETL pipelines are created using dataflows and Azure Data Factory for scalable data management. Custom APIs are developed for integrating proprietary systems. Power BI development services also employ DirectQuery for live connections and Import mode for optimized performance. These techniques ensure that data from various sources is harmonized, enabling businesses to derive insights from a centralized, real-time, and consistent data environment.