The 15th scientific seminar “Modern Demography” was held on 24 April 2019. The speaker was Johan Mackenbach, MD, PhD, Professor of Public Health, Chair of the Department of Public Health at Erasmus MC, University Medical Center Rotterdam. His report was devoted to health inequalities in Europe, their scope, trends, spatial features and factors determining them. A separate question of the seminar - why the Western European welfare state could not eradicate differences in mortality depending on the socio-economic status of a person?