Over the past three decades, a major change has occurred in economic thinking. No longer do we consider the economic process of producing goods and services and generating human welfare to be solely dependent on the accumulation of physical and human capital. An increasing number of economists now accept that there is a third form of “capital” or “economic asset” that is also crucial to the functioning of the economic system of production, consumption and overall welfare. This distinct category consists of the natural and environmental resource endowment available to an economy, which is often referred to as natural capital.