Organization owners, and members with admin privileges for a repository, can invite outside collaborators to work on the repository. You can also restrict outside collaborator invite permissions to only organization owners.
- In the top right corner of GitHub AE, click your profile photo, then click Your profile.
- On the left side of your profile page, under "Organizations", click the icon for your organization.
- Under your organization name, click Settings.
- In the left sidebar, click Member privileges.
- Under "Repository invitations", select Allow members to invite outside collaborators to repositories for this organization.
- Click Save.