Arcot Ramachandran (1923-2018) was an Indian scientist, anthropologist, author and a former Under-Secretary General of United Nations Centre for Human Settlements, known for his scholarship on the subjects of heat and mass transfer and environment and his social commitment to the cause of sustainable development. The Government of India honoured him in 2003, with the Padma Bhushan, the third highest civilian award, for his services to the fields of Science and Engineering. Life sketch Born in a Tamil speaking Arcot Mudaliar family in the Indian state of Karnataka, Arcot Ramachandran graduated from the Madras University and went to the Purdue University, USA, from where he obtained MS degree in Engineering. He continued at the University for his doctoral research and obtained his PhD. Ramachandran started his career as a faculty member of the Department of Power Engineering at the Indian Institute of Science, Bangalore, in 1950, and, later, rose to the rank of an Assistant Professor. In 1954, he took a break from the teaching career to work as a Research Engineer at Babcock & Wilcox Research and Development Centre, Renfrew, Scotland where he worked for a year. The next year, in 1955, he again went to the US to continue his studies at the post-doctoral level, as post-doctoral research fellow, to Purdue University and, later, at Columbia University. Ramachandran came back to India, in 1957, did a summer course at Indian Institute of Technology, Madras. Subsequent to that, IISc invited him to head the Department of Mechanical Engineering. In 1965, he was transferred as the Head of the Department of Industrial Management and, two years later, in 1967, he became the Director of IIT Madras. In 1973, the Government of India established a new Department of Science and Technology and nominated Dr. Ramachandran as the Government Secretary and the Director-General of the Council of Scientific and Industrial Research, in charge of the newly formed department. During his tenure there, he is reported to be able to start several ventures and programs such as: Science and Technology Agency Environment Planning, Co-ordination and Research Programme Science and Engineering Research Council Energy Sources Research and Development Programme National Information System for Science and technology (NISSAT) Central Electronics Limited In 1977, Ramachandran was made the chairman of the Preparatory Committee for the United Nations Conference on Science and Technology for Development. He was also involved with the UNESCO Expert Group Meeting on Engineering