Dr. Ravindra Rao is Assistant Professor of Psychiatry at NDDTC, AIIMS, New Delhi. A psychiatrist by training, Dr. Rao has worked in NACO, as well as in UNODC, Regional Office for South Asia, New Delhi and assisted in initiating and scaling-up OST programme in India as well as other South Asian Countries. He has also developed various documents related to OST including practice guidelines, standard operating procedures, and training modules. He has trained several OST service providers in India. He has authored several publications on substance use disorders