An audit comprises the systematic review of a management system set up in a company (e.g. a quality management system) or a component thereof (e.g. a process or a legal requirement). As a rule, the degree of fulfilment of requirements is assessed with an evaluation divided into classes. Audits are carried out by external certification organizations as a basis for certification, but it is also the company’s responsibility to carry out regular audits of individual areas and processes to check the effectiveness of the management system and continuously develop it further.