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Yes, with an Azure Government account, you can grant access to your Azure DevOps projects to users from other government organizations. This is achieved through cross-tenant access configurations in Microsoft Entra ID.
https://learn.microsoft.com/en-us/entra/external-id/cross-tenant-access-overview
https://learn.microsoft.com/en-us/entra/external-id/b2b-government-national-clouds
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