The service also has a GetTenantByExternalId( CHARACTER ) method that allows you to retrieve a tenant by a user-defined external id.
Note: The ExternalId property is not defined as a unique key and GetTenantByExternalId( ) will throw an error if more than one tenant is found with the requested external ID. One can use GetTenants( ) with a filter to retrieve a collection of tenants with a specific external ID.
