Nikolai Dmitriyevich Kondratiev (1892 – 1938) was a Russian economist who is best known for his theory of cycles within the western capitalist economies. These cycles, or long-waves are commonly referred to as Kondratiev or K-Waves and are asserted to have an approximate duration of 50-60 years. Kondratieff based his theory upon the hypothesis that at the early stage of an economic cycle, large volumes of high cost capital goods are produced along with large amounts of infrastructure spending, this leads to an increasing demand for consumer goods as new employment and increased spending is generated. After several decades the expected return on investment begins to fall below the level of interest rates. This, in turn, leads to a contraction in investment resulting in large-scale layoffs and a reduced demand for capital goods which have reached a level of over-capacity. Unemployment and economic crises ensue as the economy begins to contract. Both individuals and companies begin to save capital and resources as confidence runs low and the whole process only begins again once sufficient levels of both capital and confidence are present to prompt large-scale investment, only then does a new cycle emerge.