Hi Pat, Thanks for reaching out to community.databricks.com.

yes, service principles can be used for Unity Catalog. https://docs.databricks.com/data-governance/unity-catalog/index.html#identity-management-for-unity-c...

Also for other Databricks identities and roles, please refer : https://docs.databricks.com/administration-guide/users-groups/index.html

For managing groups users, and service principles,. please refer below:

https://docs.databricks.com/administration-guide/users-groups/users.html