The National Sample Survey Office (NSSO), formerly called the National Sample Survey Organisation is the largest organisation in India conducting periodic socio-economic surveys. It is under the Ministry of Statistics of the Indian government. Set up in 1950, the employees of the NSSO are from the Indian Statistical Service (appointed through the UPSC) and the Subordinate Statistical Service (appointed through the Staff Selection Commission). The NSSO conducts large-scale sample surveys throughout India. It is headed by a Director General. The four divisions of the NSSO are: Survey Design and Research Division, Field Operations Division, Data Processing Division and Co-ordination & Publication Division.