Import & export
Moving customers in and out by CSV.
The directory moves in both directions as CSV: import to bring an existing customer list in, export to take the whole directory out.
Who can do this: importing needs the customer create permission; exporting needs only view — the export button lives under the directory's More actions.

Download template gives you the column layout. The rules are few:
The import is a two-step: Validate file checks everything and writes nothing, reporting every problem with the spreadsheet's own row numbers — including duplicates within the file ("duplicate email — already used on row N of this file") and clashes with customers already in the directory. Then either fix the file, or press Import valid rows to load the clean rows and leave the flagged ones behind.
The result toasts are the honest summary: "Every row is valid. Review the summary, then import." or "Some rows need attention. Fix them, or import the valid rows only."
Export downloads the whole directory as CSV — every customer, whatever the current tab or filters show. It is the right first step before anything irreversible.
The column-by-column reference lives at CSV templates.