The job of Delimitation Commission headed by Justice Kuldeep Singh was to redrawn the boundaries of electoral constituencies. In last delimitation in 1975 (using the 1971 Census), the number of elected Lok Sabha seats increased from 490 to 543.
However, the special (42nd )Amendment to the Constitution in 1976 deferred further delimitation till after the 2001 Census.The task of Delimitation Commission to redrawn boundaries on the basis of the 2001 population.
Under Article 82 of the Indian Constitution, the Parliament enacts a Delimitation Act after every census. Then, the Government constitutes a Delimitation Commission. This Delimitation Commission redrawn the boundaries of the Parliamentary Constituencies .