Industrialisation (UK) or industrialization (US) is "the period of social and economic change that transforms a human group from an agrarian and feudal society into an industrial society. This involves an extensive reorganisation of an economy for the purpose of manufacturing." Industrialisation is associated with increase of polluting industries heavily dependent on fossil fuels. With the increasing focus on sustainable development and green industrial policy practices, industrialisation increasingly includes technological leapfrogging, with direct investment in more advanced, cleaner technologies.

The reorganisation of the economy has many unintended consequences both economically and socially. As industrial workers' incomes rise, markets for consumer goods and services of all kinds tend to expand and provide a further stimulus to industrial investment and economic growth. Moreover, family structures tend to shift as extended families tend to no longer live together in one household, location or place.

The first transformation from an agricultural to an industrial economy is known as the Industrial Revolution and took place from the mid-18th to early 19th century. It began in Great Britain, spreading to Belgium, Switzerland, Germany, and France and eventually to other areas in Europe and North America. Characteristics of this early industrialisation were technological progress, a shift from rural work to industrial labour, and financial investments in new industrial structures. Later commentators have called this the First Industrial Revolution.

The "Second Industrial Revolution" labels the later changes that came about in the mid-19th century after the refinement of the steam engine, the invention of the internal combustion engine, the harnessing of electricity and the construction of canals, railways, and electric-power lines. The invention of the assembly line gave this phase a boost. Coal mines, steelworks, and textile factories replaced homes as the place of work.

By the end of the 20th century, East Asia had become one of the most recently industrialised regions of the world.

There is considerable literature on the factors facilitating industrial modernisation and enterprise development.

The Industrial Revolution was accompanied by significant changes in the social structure, the main change being a transition from farm work to factory-related activities. This has resulted in the concept of Social class, i.e., hierarchical social status defined by an individual's economic power. It has changed the family system as most people moved into cities, with extended family living apart becoming more common. The movement into more dense urban areas from less dense agricultural areas has consequently increased the transmission of diseases. The place of women in society has shifted from primary caregivers to breadwinners, thus reducing the number of children per household. Furthermore, industrialisation contributed to increased cases of child labour and thereafter education systems.

As the Industrial Revolution was a shift from the agrarian society, people migrated from villages in search of jobs to places where factories were established. This shifting of rural people led to urbanisation and an increase in the population of towns. The concentration of labour in factories has increased urbanisation and the size of settlements, to serve and house the factory workers.