On Eval Setup you can search for external courses and include them

If you select a course that already exists in the database, it will inform you that it is already being managed by another department (and will tell you which one) and you can't also manage it in your dept.

You can also select an external course and then selectively only evaluate specific sections of that course (though the entire course will be assigned to your dept).

@anlai The "Add Course From External Department" button and the modal's "Add Course" button upon finding a valid course could use a quick design look.