Lucy Ash profiles the Russian lawyer and anti-corruption campaigner Alexei Navalny, who this week topped a ballot to elect leaders of the opposition to President Putin.
He came to prominence as a leader during the anti-Putin demonstrations in Moscow last December, the biggest such rallies since the end of the Soviet Union.
He has also been fighting against corruption through a website that invites the public to report suspected cases to the police or prosecutors.
One of his tactics, was to become a minority shareholder in major Russian oil companies, banks, and ministries to ask awkward questions about holes in state finances. Those holes are huge. Last year Dmitri Medvedev - then President now PM - said that a trillion roubles-thirty-three billion dollars- disappears annually on government contracts.
Aleksey Navalny's anti graft campaign has won him popularity across a wide spectrum of Russian society, including nationalists with far right connections. This has unsettled many of more liberal supporters. And in a week when three other opposition activists have been charged with causing mass unrest, does he have what it takes to challenge the tough man in the Kremlin?
Producer Arlene Gregorius.