SQL Server Integration Services (SSIS) is a platform for building enterprise-level data integration and workflow solutions. It features graphical tools and wizards for quickly building and debugging packages to automate workflows. SSIS facilitates data migration, data cleansing, and ETL (extract, transform, load) operations across a wide range of data sources. Its extensible architecture supports integration with various applications and services, making it a versatile tool for managing and processing data efficiently in organizations.