Accreditation or certification is a recognition given to an operation or product that has been evaluated against a standard; be it regulatory or voluntary. The purpose of accreditation is to provide the consumer with a level of confidence in the quality of operation (process) and the product of an organization. Environmental Protection Agency/OCM has proposed the development of an accreditation program under National Environmental Laboratory Accreditation Program for Good Laboratory Practice (GLP) laboratories as a supplement to the current program. This proposal was the result of the Inspector General Office reports that identified weaknesses in the current operation. Several accreditation programs can be evaluated and common components identified when proposing a structure for accrediting a GLP system. An understanding of these components is useful in building that structure. Internationally accepted accreditation programs provide a template for building a U.S. GLP accreditation program. This presentation will discuss the traditional structure of accreditation as presented in the Organization of Economic Cooperative Development/GLP program, ISO-9000 Accreditation and ISO/IEC Guide 25 Standard, and the Canadian Association for Environmental Analytical Laboratories, which has a biological component. Most accreditation programs are managed by a recognized third party, either privately or with government oversight. Common components often include a formal review of required credentials to evaluate organizational structure, a site visit to evaluate the facility, and a performance evaluation to assess technical competence. Laboratory performance is measured against written standards and scored. A formal report is then sent to the laboratory indicating accreditation status. Usually, there is a scheduled reevaluation built into the program. Fee structures vary considerably and will need to be examined closely when building a GLP program.