The Chennai Metropolitan Development Authority (CMDA), formerly known as the Madras Metropolitan Development Authority (MMDA), is the nodal planning agency of Chennai in the Indian state of Tamil Nadu. The CMDA administers the Chennai Metropolitan Region, spread over an area of 5,904 km2 (2,280 sq mi) and covers the districts of Chennai, Thiruvallur, Chengalpattu, Ranipet and Kancheepuram. It was set up for the purposes of planning, co-ordination, supervising, promoting and securing the planned development of the Chennai Metropolitan Area. It coordinates the development activities of the municipal corporations, municipalities and other local authorities.

Chennai, formerly known as Madras, is the capital city of Tamil Nadu, the southernmost state of India. It is the state's primate city and is located on the Coromandel Coast of the Bay of Bengal. According to the 2011 Indian census, Chennai is the sixth-most populous city in India and forms the fourth-most populous urban agglomeration. Incorporated in 1688, the Greater Chennai Corporation is the oldest municipal corporation of India and the second oldest in the world after London.