Accreditation is the process in which certification of competency, authority, or credibility is presented.
Organizations that issue credentials or certify third parties against official standards are themselves formally accredited by accreditation bodies; hence they are sometimes known as "accredited certification bodies". The accreditation process ensures that their certification practices are acceptable, typically meaning that they are competent to test and certify third parties, behave ethically and employ suitable quality assurance.
Accreditation is a third-party attestation related to a conformity assessment body conveying formal demonstration of its competence to carry out specific conformity assessment tasks (definition according to EN ISO/IEC 17000).
Accreditation provides confidence in the value and credibility of the various types of conformity assessment and represents the last level of control of the validity of conformity assessment services in both voluntary and regulated areas.
Reference: European Committee for Standardization