> For the complete documentation index, see [llms.txt](https://documentation.immuta.com/2024.2/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://documentation.immuta.com/2024.2/secure-your-data/projects-and-purpose-based-access-control/masked-joins/enable-masked-joins.md).

# Enable Masked Joins

While masked joins are allowed, only project owners can add data sources to the project. Additionally, masked columns can only be joined if they are masked using hashing.

In order to join mask columns across data sources, those data sources must be linked by a project.

**Requirement**: You must own the project

1. [Create a project](/2024.2/secure-your-data/projects-and-purpose-based-access-control/projects-and-purpose-controls/how-to-guides/create-project-tutorial.md) or select an existing project.
2. Navigate to the **Overview** tab.
3. Click the **Allow Masked Joins toggle**.
4. Click **Confirm**.


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