# Roles and permissions There are several possible roles in a Zulip organization. * **Organization owner**: Can manage users, public streams, organization settings, and billing. * **Organization administrator**: Can manage users, public streams, and organization settings. Cannot create or demote organization owners. * **Moderator**: Have the permissions of full members; additionally, many **Organization permissions** settings allow moderators to be given additional privileges or do so by default. * **Member**: Has access to all public streams. Member is the default role for most users. [Some organization settings](/help/restrict-permissions-of-new-members) allow an organization to restrict the permissions of **new members**; Members who do not have those restrictions are called **full members**. * **Guest**: Can only view or access streams they've been added to. [Guest users](/help/guest-users) interact with public streams as though they were private streams with shared history. Cannot create new streams or invite other users. * **Billing administrator**: The user who upgrades the organization to a paid plan is, in addition to their normal role, a billing administrator. Can manage billing in addition to the existing privileges. This allows someone from the billing department to manage billing without needing organization administrator permissions. For details of the access control model, see [Stream permissions](/help/stream-permissions). You can decide what role to invite a user as when you [send them an invitation](/help/invite-new-users). Organization owners can do anything an organization administrator can do. For brevity, we may sometimes refer to "organization administrators" being able to do something; unless stated explicitly, this means "organization owners and administrators" can do that thing. ## Related articles * [Stream permissions](/help/stream-permissions) * [Inviting new users](/help/invite-new-users) * [Zulip Cloud billing](/help/zulip-cloud-billing) * [Guest users](/help/guest-users)