The Hawthorne experiments were a series of studies conducted at the Western Electric Company’s Hawthorne Works in Chicago between 1924 and 1932. They are closely associated with Elton Mayo and his colleagues and played a major role in the development of the Human Relations approach to public administration and organizational theory. The experiments examined the relationship between working conditions, productivity, employee attitudes, and social relationships within organizations. The first major study was the Illumination Experiment, conducted between 1924 and 1927. Researchers attempted to determine whether changes in workplace lighting affected worker productivity. The intensity of light was increased for one group of workers and kept constant for another group. Surprisingly, productivity increased not only when lighting was improved but also when it was reduced. This suggested that physical conditions alone could not explain changes in productivity. The researchers began to recognize that psychological and social factors could significantly influence employee behaviour. The second important study was the Relay Assembly Test Room Experiment,