Das served in various positions for both the Government of India and the Government of Tamil Nadu, like as Principal Secretary (Industries), Special Commissioner (Revenue), Secretary (Revenue), Secretary Commercial Taxes, the project director of Tamil Nadu State AIDS Control Society and as the district magistrate and collector of Dindigul and Kancheepuram districts in the Tamil Nadu government; and as Union Economic Affairs Secretary, Union Revenue Secretary, Union Fertilizers Secretary, Special secretary in the Department of Economic Affairs of the Ministry of Finance and as a joint secretary in the Department of Expenditure of the Ministry of Finance in the Indian government.