This is the crucial stage which covers a relatively brief period of two to three decades in which the economy transforms itself in such a way that economic growth subsequently takes place more or less automatically. “The take-off” is defined as “the interval during which the rate of investment increases in such a way that real output per capita rises and this initial increase carries with it radical changes in the techniques of production and the disposition of income flows which perpetuate the new scale of investment and perpetuate thereby the rising trend in per capita output.”