Abstract: Business intelligence (BI) is considered to have a high impact on businesses. Research activity has risen in the last years. An important part of BI systems is a well performing implementation of the Extract, Transform, and Load (ETL) process. In typical BI projects, implementing the ETL process can be the task with the greatest effort. Here, set of generic metamodel constructs with a palette of frequently used ETL activities, is specialized , which are called templates.