In environmental science, the concept of overrun means demand greater than regeneration. It can refer to animal and human populations. Scientific studies of the environment in which the extent of the human population has risen above the sustainable use of resources by its resource consumption. For humans, “exaggeration” is that part of their demand or environmental footprint that must be eliminated in order to be sustainable. Excessive demand that leads to overruns is also driven by consumption. One of the main problems is the ecological debt on which almost the whole world lives. The day of ecological debt is calculated on the basis of how much water, forests, metals and other resources are available on the planet and how fast they are consumed. If we take all the resources as the principal that is available to us during one year, when we exceed it, an ecological debt arises. The topic of this paper will deal with the ecological debt. The paper consists of a total of 5 chapters. The first chapter is an introduction in which the subject and goal of the research and the purpose of the work are defined. Furthermore, the introduction provides an overview of data collection methods and an overview of the work structure. The introduction is followed by a chapter that defines life beyond the boundaries of nature and sustainable development, but also defines all the other key concepts that are very important to understand the essence of the topic. Namely, this chapter will define the above terms, as well as the International Conventions on Sustainable Development and global awareness. Furthermore, the chapter will show the value of nature and the environment and will define Earth Day. The third chapter defines the ecological footprint and its history. The chapter provides a historical overview, methodology and measurement of the ecological footprint. The fourth chapter presents research based on a comparison of the ecological footprint of selected EU countries. After the analysis of the research, a conclusion is made in which everything that was written in the paper will be summarized and lead to conclusions that are important for the Ecological Debt Day itself and how to reduce the ecological debt