Seshan was appointed CEC on December 12, 1990 during the P V Narasimha Rao led Congress government.
He is widely credited for bringing in electoral reforms that changed the face of Indian elections.
One of them was the implementation of the Model Code of Conduct, which is a set of guidelines issued to regulate political parties and candidates prior to elections.
The rules range from issues related to speeches, polling day, polling booths, portfolios, content of election manifestos, processions and general conduct, so that free and fair elections are conducted.