The QS scheme comprises various types of audit, each with a different focus. The regular audit forms the basis for certification and comprehensively assesses whether a company meets all QS requirements. In addition, for certain production scopes, unannounced spot audits are carried out between regular audits. These focus primarily on the production process. In addition, random sample audits are carried out on a regular basis to monitor specific criteria. There are also parallel and witness audits. Through these, QS reviews the work of certification bodies and auditors and strengthens the integrity of the scheme. In cases of suspicion or imminent danger, audits of special purpose are carried out to investigate the matter on site.