François Perroux's 'growth pole' theory, developed in 1955, is a significant contribution to understanding economic growth and regional development, particularly through the concept of 'forward and backward linkages.' Perroux argued that economic development does not appear everywhere at once but manifests in specific 'growth poles' or 'growth centers'—dynamic, propulsive industries or firms that drive growth in their surrounding regions.

These propulsive industries are typically large, innovative, and technologically advanced, possessing strong inter-industry relationships that generate multiplier effects throughout the economy. These relationships are categorized as:

1. Backward Linkages: These occur when a propulsive industry creates demand for inputs (raw materials, components, services) from other industries. The growth of the propulsive industry stimulates the development and expansion of its supplier industries. For example, a new automobile manufacturing plant (the growth pole) will create a demand for steel, tires, glass, electronics, and various services, thereby fostering the growth of these 'backward-linked' industries in the region.

2. Forward Linkages: These arise when the outputs of a propulsive industry serve as inputs for other industries. The availability of these outputs facilitates the development of industries that use them in their production processes. For instance, a steel mill (the growth pole) provides steel to automobile manufacturers, construction companies, and appliance makers, thereby encouraging the growth of these 'forward-linked' industries.

Together, these forward and backward linkages create a chain reaction of economic activity. The propulsive industry's expansion leads to increased production and employment in both its supplying and consuming industries, spreading economic growth from the core pole to the periphery. This process fosters agglomeration economies, attracting more businesses and labor to the region, and ultimately contributing to regional development, albeit sometimes unevenly.