---
title: Integrate external system
slug: cms-12/docs/integrating-forms-with-external-systems
docTags: 
createdAt: 2026-08-10T15:56:04.000Z
---

:::hint{type="info"}
**Note**
[Optimizely Forms](docId:3SbSlJZIS_3iFmghfQA3J) is only supported by MVC-based websites and HTML5-compliant browsers.
:::

Optimizely Forms includes an Autofill API (Beta) and an External System Mapping API (Beta), opening up several integration points to cooperate with another system (especially Marketing Automation, CRM, and so on).

The following links show open-sourced sample code:

- [http://github.com/episerver/EPiServer.Forms.Samples](http://github.com/episerver/EPiServer.Forms.Samples)
- [http://github.com/episerver/EPiServer.Forms.Demo](http://github.com/episerver/EPiServer.Forms.Demo)The sample for `IExternalSystem` and `IAutofillProvider` is in the Forms Demo project.

![](https://api.archbee.com/api/optimize/BrbvVORKJ5iIeSMZye5kI/ZGX3bPGPEK3i9yvxhhzEi-20260722-170226.png "episerver-forms-diagram.png")