1. To view entities currently synchronizing with Data Sources,click Synchronized.
2. To add or remove the fields that synchronize between your Contact Builder configuration and the synchronized data source, click Edit Fields. This action affects the data available to your activities in other Marketing Cloud apps. Ensure that your changes do not adversely affect these activities before you make your changes.
3. Click the checkbox next to fields to synchronize. This screen displays mandatory fields for the synchronization process as checked fields in gray.
4. Click Save. The synchronization process takes some time to complete.