He was also the driving force behind the Vodafone's strategic move into emerging markets, especially Asia and Africa, through the purchases of Turkish operator Telsim and a controlling stake in Hutchison Essar in India.
He subsequently became chief executive of InfoSpace in 2000 and of Accel-KKR Telecom based in San Francisco from 2001 to 2003, while serving as a non-executive director of Vodafone.
He rejoined Vodafone as chief executive designate on 1 April 2003 and was appointed on a permanent basis after the company's annual general meeting on 30 July 2003.
[citation needed] During his tenure as chief executive of Vodafone group plc, he expanded the company geographically into countries like India, Turkey, South Africa etc.
[citation needed] Sarin retired from Vodafone immediately after the company's annual general meeting on 29 July 2008, and was succeeded by then deputy-CEO Vittorio Colao.
He is currently an investor and adviser to a number of early stage technology companies based in the San Francisco Bay Area and India.