A Data Transformation Services (DTS) developer designs, develops, and maintains applications that automate data extraction, transformation, and loading (ETL) processes. They work with databases and data warehousing, handling tasks like cleansing, aggregating, and integrating data from diverse sources. They use DTS tools to create packages for automating tasks, such as copying databases, populating data warehouses, and processing data. They also ensure data integrity and security, troubleshoot issues, and optimize performance. Additionally, they collaborate with other IT professionals like data analysts and database administrators to create effective data management solutions.