Managing membership in your organization
After you create your organization, you can invite people to become members of the organization. You can also remove members of the organization, and reinstate former members.
Inviting users to join your organization
You can invite anyone to become a member of your organization using their username or email address for GitHub.com.
Canceling or editing an invitation to join your organization
Organization owners can edit or cancel an invitation to become a member of your organization any time before the user accepts.
Removing a member from your organization
If members of your organization no longer require access to any repositories owned by the organization, you can remove them from the organization.
Reinstating a former member of your organization
You can invite former organization members to rejoin your organization, and choose whether to restore the person's former role, access permissions, forks, and settings.
Exporting member information for your organization
You can export information about all of your organization's members from GitHub's web UI.
Can I create accounts for people in my organization?
While you can add users to an organization you've created, you can't create personal accounts on behalf of another person.