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Use cases → Admin and governance

Synchronise a company-wide contact list for all users

Push a master address book into every user's Google Contacts using a delegated service account and the People API.

Who it is forIT admins maintaining a single source of truth for internal and external contacts.
APIsAdmin SDK, People API
Typical scopesadmin.directory.user.readonly, contacts

The problem

Users need up-to-date contact details for colleagues and key partners, but manual updates and CSV imports go stale instantly and are error-prone.

How it works

  1. Maintain a master contact list in a central system or spreadsheet.
  2. Use the Admin SDK to enumerate all active users in the domain.
  3. For each user, impersonate their account via domain-wide delegation.
  4. Push or update the relevant contacts into each user's Google Contacts using the People API.

What changes

Every user sees the same, up-to-date contacts in their address book, reducing lookup friction and misdirected mail.

The trap in this one. The People API's contact insert and update operations are eventually consistent and can silently drop updates if the same resource is written in rapid succession. When running a bulk sync, rapid-fire updates to the same user's contacts may result in some changes simply not appearing, with no error returned. Always batch and rate-limit writes per user, and verify by reading back a sample after the operation.

Questions people ask

Can you remove stale contacts?

Yes, but you must track which contacts were system-managed versus user-created, typically by using a unique identifier in a custom field or the notes.

Does this overwrite user changes?

If you update by contact ID, you can overwrite fields, but users may still edit or delete synced contacts unless you enforce regular reconciliation.

Want this built?

This is a pattern we run in production. We will set up the delegation and build this on top of it — $500 per hour, most of it working the same day.

Talk to us Or read the setup guide

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