A quality control (QC) system is needed in ART units to assure reproducibility of all methods and competence in all duties performed by the personnel. The necessity of a quality control system becomes even clearer when considering the possible risks of ART. It is therefore essential to have a system to assure that everybody knows exactly how everything should be done. Furthermore, a QC system should bring about improvements such as making activities and procedures clearer to the staff and making the working methods more flexible. QC was initially created for the industry, and has later been applied to other types of activities such as management of organizations, services like health care including different types of clinical testing laboratories. To maintain a high standard in our IVF laboratory, and to assure reproducibility of the methods used we decided to apply for accreditation according to the European Norm (EN) 45001 and requirements for the competence of testing laboratories ISO/IEC Guide 25. A process was started where all routines and methods within the laboratory were documented and finally the QC system was described in a quality manual. Application for accreditation was submitted to the Swedish board for accreditation and conformity assessment (SWEDAC). Our ART laboratory finally became accredited according to the EN 45001 and requirements for the competence of testing laboratories ISO/IEC Guide 25. Introducing and fully implementing a quality control system in our laboratory has standardized the methods and the way that the embryologists perform their work in the laboratory. It has also optimized the environment in which the patient's gametes and embryos are handled.