Delimitation literally means the act or process of fixing limits or boundaries of territorial constituencies in a country or a province having a legislative body.
In India, such Delimitation Commissions have been constituted 4 times - in 1952 under the Delimitation Commission Act, 1952, in 1963 under Delimitation Commission Act, 1962, in 1973 under Delimitation Act, 1972 and in 2002 under Delimitation Act, 2002.
Under Article 82 of the Constitution, the Parliament by law enacts a Delimitation Act after every census. After coming into force commencement of the Act, the Central Government constitutes a Delimitation Commission.
This Delimitation Commission demarcates the boundaries of the Parliamentary Constituencies as per provisions of the Delimitation Act.
The present delimitation of constituencies has been done on the basis of 2001 census figures under the provisions of Delimitation Act, 2002. Notwithstanding the above, the Constitution of India was specifically amended in 2002 not to have delimitation of constituencies till the first census after 2026. Thus, the present Constituencies carved out on the basis of 2001 census shall continue to be in operation till the first census after 2026.
The Delimitation Commission in India is a high power body whose orders have the force of law and cannot be called in question before any court. These orders come into force on a date to be specified by the President of India in this behalf. The copies of its orders are laid before the House of the People and the State Legislative Assembly concerned, but no modifications are permissible therein by them.