One of the criticisms of self-certification or manufacturer's declaration, namely that the manufacturer does not have a third party checking the competence and integrity of the results, fails to recognize that many third party certification programs also do not have anyone looking over their shoulder to ensure the quality of their programs. Like a laboratory, a certifier can self-declare or self-certify its compliance with the requirements, such as those listed in ISO Guide 65: 1996 "General requirements for bodies operating product certification systems." Users of certification results can also validate a certifier's compliance for themselves. Yet another method for ensuring the competence of certifiers is through an accreditation program conducted by an independent third party. A third party (independent of the certifier and the purchasers or users of the certification) can accredit the competence of a certifier to conduct specific certification tasks for specific types of products. Like laboratory accreditation, certification program accreditation does not necessarily give any guarantees about the certification results obtained from the performance of specific certification procedures. Certification program accreditation means that the certifier is capable of performing specified certification procedures correctly, not that the certifier has competently certified all products in each and every instance. Again, like laboratory accreditation, certification program accreditation only provides assurance about a certifier's capability within the scope or areas for which accreditation was granted. It should also be noted that lack of accreditation does not necessarily imply that the certifier is not technically competent since not all certifiers want or require accreditation. In some cases, accreditation programs may not exist in the certifier's field of operation.

Meeting regulatory requirements is again probably the primary reason for a certifier to participate in an accreditation program. Congress, state and local governments can mandate that certifications be done by accredited certifiers. OSHA, for example, is responsible for the regulation of all electrical products used in the work place. Electrical products under OSHA's jurisdiction require approval and marking/listing by certifiers accredited by OSHA, known as Nationally Recognized Testing Laboratories (NRTL).

State and local government agencies may also impose such a requirement through regulations issued under their own legal authority. Certifiers may also have to be accredited to meet mandatory requirements imposed by foreign governments on products imported into their countries.