Circular economics (CE) is increasingly discussed among researchers, practitioners, and politicians. The discussions between the parties and the confusion about the concept cause the issue to remain on the agenda. According to the general view, CE is the slowing, shrinking, and closing of the welding flow to increase the welding efficiency. However, little attention has been devoted to measuring the CE level of a given economic system. The aim of this chapter is to demonstrate the emergence and development process of CE, and also to show how the CE level of any economic system can be measured. In this context, it is important for developing countries to interest with the issue but not in practice. To put this into perspective, the study examined Turkey's economic system. Turkey's economic, environmental, and social indicators examined were found to have a remote structure of the CE principle. It is expected that the results of the study will lead to a positive social change and become a framework for increasing the contribution of developing economies to the sustainable world.