It all began with the opening of the Calcutta Normal School in India on 1 March 1852. It was a joint vision of two young women, one was the wife of an English merchant in Calcutta and the other the wife of a wealthy English banker in Britain. The school trained women to teach other women who are secluded from the outside world in the zenanas at home.

The work gradually spread to neighbouring countries, such as Pakistan (following the Partition of British India) and Nepal, which was completely closed to Christianity until the 1950s (the Nepali Church now consists of over 400,000 people). In 1952, men were accepted as workers for the first time – until then, only women had been allowed to join. The work has spread, and Interserve workers are sent from many countries, including Singapore, UK and Ireland, Germany, Switzerland, the Netherlands, the USA, Canada, Australia, New Zealand, India, Malaysia, Hong Kong, South Korea and Brazil.