T. L. Sankar joined as the Principal of Administrative Staff College of India in 1993 after his superannuation from the Indian Administrative Service for 35 years. During his tenure with the Government, he held important positions both at the national and state level. In Andhra Pradesh, he was the Principal Secretary in the departments of Industry and Finance and was Chairman of Andhra Pradesh Electricity Board. For twelve years, he also held additional charge of the Directorship of Institute of Public Enterprise.
In Government of India, he was the Chief of the Project Appraisal Division and Advisor, Energy to the Planning Commission of India. He was associated in Delhi with all initiatives in the Energy Sector. He was Secretary of the Fuel Policy Committee, 1975, Working Group on Energy, 1979 and as the Member of the Integrated Energy Policy Committee 2005. He was Chairman of the Gas Price Revision Committee 1997 and the Expert Committee on Coal Reforms 2007. He has been a Director on many Government of India Public Sector Organisations such as NTPC, HPCL, NALCO, IREDA.
He was awarded the Padma Bhushan in recognition of his services to the country as a civil servant.
He was a Consultant to Asian Development Bank, United Nations, and World Bank on Energy and Development Issues and has served on short time assignments in Sri Lanka, Jamaica, Tanzania, Ghana and other countries. He has many publications to his credit in the Indian and Foreign Journals. He is currently an Honorary Visiting Professor at ASCI and associated with a number of NGO organisations in the country.