Most natural resources that are used in production are non-renewable. When they become depleted they are lost for future use. Does it follow that the limited availability of natural resources will at some time in the future constrain economic growth as many environmentalists believe? While classical economists have shared the belief in limits to growth, the distinctive feature of modern neoclassical economics is its optimism about the availability of natural resources. After demonstrating the major role natural resources play in all economies worldwide (in the first part), we revealed the national and international character of natural resources (in the second part), with special focus on the international trade with resources and goods that may alleviate temporary shortages in supplying with raw materials and energy resources of any economy. In the end, the paper dealt with the old controversy between unlimited needs (of economies and of population) and the limited resources (especially of non-renewable natural resources), as their availability is questioned more and more in the present days. Special focus was placed on natural resources scarcity as this is the most pregnant element showing the limitations natural resources must face today. To better understand this issue, an econometric model was given to demonstrate the strong link between the actual stock of natural resources, on one hand, and the increase in exploitable stock due to the geological and soil improvement activity, as well as the raw material and energy production, on the other hand. In the end, some arguments were given to strengthen the need for sustainable development and environmental protection as the sole way to deal with inter-generational allocation of natural resources, which is, in fact, the basis of sustainability.
