While configuration and integration are important, without data you do not have a completed system. And too often data migration is not given a priority and causes a delay. With our Data Migration methodology, we actually do migration four times (Iteration 3, UAT, Parallel and Prod) using an ETL tool and a dedicated migration instance. This way data migration is a visible part of the project activities and the data migration team becomes familiar with the system configuration and understand where country specific data extraction and conversion rules are needed.