On the one hand, the paper attempts to determine the complex phenomenon of competitiveness of countries conceptually and essentially, and on the other hand, it presents the competitiveness of the ten most competitive countries in the world, Serbia and 8 selected countries, according to Global Competitiveness Index 4.0. A wide range of views of economic theorists, concerning the justification of using the concept of country competitiveness, was stated. The position on the justification of treating the competitiveness of countries was stated and it was concluded that the basis of this concept is the increase in productivity as the most important determinant of long-term economic growth, i.e. the improvement of all significant factors that enable more efficient use of factors of production. The concept is based on the observation of economic growth as the sum of growth factors of production - i.e. labor and capital - and total factor productivity, as measures of factors that cannot be explained by labor, capital or other inputs. Also, the paper provides an analysis of the indicators of competitiveness and innovation ability of the ten most competitive countries in the world, the Republic of Serbia and selected countries from its surroundings in 2019, based on data from the World Economic Forum. It was stated that Serbia and the countries from its surroundings lag far behind the most competitive and most innovative countries in the world. However, a relatively favorable position of Serbia in terms of innovation capacity was noted, which leaves room for Serbia to make significant and faster progress in terms of improving international competitiveness than most of the observed countries in the region.