> ## Documentation Index
> Fetch the complete documentation index at: https://docs.membrane.agency/llms.txt
> Use this file to discover all available pages before exploring further.

# Field Mappings

Field Mappings are legacy workspace elements for transforming records between Membrane and external apps. New connector work should use connector auth, workspace Actions, Data Syncs, Data Tables, and External Event Types instead.

## Configuring Field Mapping

To configure field mapping, you provide:

* External Fields define the [Data Schema](/docs/references/data-schemas) of the fields in the external app.
* Internal Fields define the schema of fields in your app. It can be generated automatically based on the mapping configuration, defined statically, or calculated dynamically via [Internal Data Schemas](/reference/workspace-elements/app-data-schemas).
* Direction: import, export, or bi-directional.
* Export Value: mapping from your app to external app.
* Import Value: mapping from external app to your app.

## Applying Field Mapping

When field mapping is applied in a Flow or an Action, the data will be transformed based on the tenant-level field mapping configuration.

You will see the mapping and the result in the Flow or Action logs.

## Learn More

<Columns cols={2}>
  <Card title="Field Mappings" href="/reference/workspace-elements/field-mappings/field-mapping-instances" target="_blank">
    Drop-in UI for a single field mapping.
  </Card>

  <Card title="Data Schemas" href="/docs/references/data-schemas" target="_blank">
    Representing data structures used in integrations.
  </Card>

  <Card title="Internal Data Schemas" href="/reference/workspace-elements/app-data-schemas" target="_blank">
    Reusing data schemas between integration elements.
  </Card>

  <Card title="Internal Events" href="/docs/managing-membrane/monitoring-troubleshooting/logs/internal-events" target="_blank">
    Reacting to events in your app.
  </Card>
</Columns>