A substitution model of technological change based upon a simple set of assumptions has been advanced. The mathematical form of the model is shown to fit existing data in a wide variety of substitutions remarkably well.

It is suggested that the model can prove useful to a number of types of investigations, such as: forecasting technological opportunities, recognizing the onset of technologically based catastrophes, investigating the similarities and differences in innovative change in various economic sectors, investigating the rate of technical change in different countries and different cultures, and investigating the limiting features to technological change.