# About Vault Migrations

A Vault migration refers to the loading of large volumes of data or documents into Vault using tools such as [Vault Loader](/en/lr/26597/) and the <a class="external-link " href="https://developer.veevavault.com/docs/#rest-api" target="_blank" rel="noopener">Vault API<i class="fa fa-external-link" aria-hidden="true"></i></a>. Migrations can be performed by customers or with assistance from Veeva's Technical Services team. For large or complicated migrations, Veeva partners with multiple <a class="external-link " href="https://www.veeva.com/meet-veeva/partners/migration/" target="_blank" rel="noopener">Certified Migration Partners<i class="fa fa-external-link" aria-hidden="true"></i></a> who use validated tools and have experience performing Vault migrations.

There are two common migration use cases:

  * **Legacy Migration**: When replacing a legacy system with Vault, it is common to migrate data from the legacy system into Vault. This type of migration usually occurs during the Vault implementation project for a new Vault, but can also happen when implementing a new application in an existing Vault.
  * **Incremental Migration**: Any business event which requires adding new data to Vault may require incremental migration. For example, a phased rollout, system consolidation, or a company acquisition. Incremental migrations occur independent of an application implementation and can affect a live production Vault application.

Learn more about best practices for planning, developing, and executing a <a class="external-link " href="https://developer.veevavault.com/migration/#vault-migrations" target="_blank" rel="noopener">Vault migration in the Developer Portal<i class="fa fa-external-link" aria-hidden="true"></i></a>.