In Belgium, a registered auditor is permitted to provide non-audit services to audit clients, on condition that his independence is not impaired. The services that an auditor cannot render have been specifically addressed in the legislation (see prohibited services). In addition to these specific services, the auditor needs to comply with the "One to One rule" (see detail below), which is only applicable for quoted companies, companies that are legally required to prepare and publish consolidated financial statements and their subsidiaries.