C. D. Sahay is a retired police officer who served as the Secretary of the Research and Analysis Wing (R&AW), India's external intelligence agency, from 1 April 2003 to 31 January 2005. He is a Karnataka cadre Indian Police Service officer of the 1967 batch.
Sahay had been in R&AW since the 1970s, when he joined the agency on a deputation. He inaugurated the present headquarters of the agency in Lodi Road, Delhi. He has undergone intelligence training in Israel and the United Kingdom.