Despite the important role of certification of persons in shaping society and a safe environment, the process of certification of persons in Latvia has been studied very little, therefore the Thesis aims to assess the process and impact factors of certification of persons as an assessment of professional compliance and competence in order to develop approaches and solutions for sustainable certification of persons. The Thesis analyzes the theoretical aspects of the concepts of certification and professional competence and their constituent elements. By assessing the mutual interaction between the elements of the certification process and the components of quality management, the problems of defining the term “certification of persons” have been studied, and the definition of the term “certification of persons” has been proposed. In order to assess the certification of persons as a service and to identify the influencing factors or barriers, for the first time in Latvia, an empirical study was conducted on the certification of persons and the assessment of professional competence carried out within it. A new sustainable approach to the certification of persons has been developed, which aims to assess professional competence and provides quality monitoring opportunities in the long term. The results of the research can be used to improve the system of certification of persons in the regulated professions not only in Latvia but also in the European Union.