The article is devoted to the analysis of the problem of defining the term “lustration” as a mechanism of personnel policy in the field of public administration. The main approaches to the interpretation of the concept of “lustration” through the prism of historical development are studied. Emphasis is placed on the understanding of lustration in ancient times and how the meaning of this term was transformed under the influence of the evolutionary development of public administration. Modern scientific approaches to the definition of lustration, its place in public administration are analyzed, its characteristic features are singled out. The author studies the scientific approaches of both foreign and Ukrainian scholars to the interpretation of the lustration, singled out the main common and distinctive features between them. It is established that the current approaches to understanding of lustration are based on three concepts. Based on the analyzed material, the author formulates his own definition of lustration as a mechanism of personnel policy in the field of public administration. The author concluded that the correct definition of lustration will help reduce differences in its application in the practice of public administration and will form a reliable mechanism for the lustration. It is determined that the legislation requires a modern understanding of the term “lustration” with the peculiarities of its implementation in a particular state.