The analytical paper presents different formulations of the concept of screening, a classification of screening types is presented. The main principles of the organization of modern screening programs for the adult population, international experience in developing recommendations, organization and conduct of screening are outlined. Examples of the variability of screening guidelines are presented. Many countries of the world have implemented and continue to implement various screening programs, but at the same time there is a process of refusing screening for certain diseases. The decision to screen for these or other diseases / risk factors varies from country to country, as the decision depends on many factors. The presence in the country of state/regional structures responsible for the formation of the list of diseases to be screened and the choice of screening methods plays a special role in making decisions about the advisability of conducting or refusing screening. The only common feature is that in no country there is no screening of the entire population for all known diseases.