This document provides an overview of migrating to Drupal from another content management system. It discusses the high-level challenges of migration versus new build projects and emphasizes taking a gradual approach. The second part details Drupal's migrate module, including its architecture, mapping functionality, and code examples for migrating content like pages and user data from other systems into Drupal. The overall guidance is that migration requires more complexity than new builds but can be achieved by going step-by-step and addressing issues discovered after launch.