Physician; 1894 joined Social-Dcmocratic movement. 1896 worked for executive of Saint St. Petersburg "League for the Liberation of the Working Class”. 1898 exiled for three years to Vyatka Province.
1902 Iskra deleg at Belostok Conference. Late 1903, after arrest and exile to Yenisey Province, escaped abroad and joined Mensheviks. 1905 returned to Russia.
Worked for ed staff, Nachalo. Took a leading part in Russian Social-Democratic Workers’ Party (Mensheviks) activities. Early 1906 with ed staff, amalgamated central organ Patiynyye izvestiya Presidium member, 4th Amalgamative Russian Social-Democratic Workers’ Party Congress in Stockholm.
At this Congress elected member, ed staff, Party central organization Headed so-called Vocalists foreign liquidationist group. Company-ed and ideological leader of their organ Golos sotsial-demokrata.
Contributed to legal liquidationist periodicals Delo zhizni, Nasha zarya. Editor, periodicals Luch, Novaya rabochaya gazeta, et cetera Before World War 1 exiled to Siberia.
During World War 1 officially centrist, but actually sympathized with defensism, demanding associate with military-industry comts. After 1917 February Revol head, Russian Social-Democratic Workers’ Party (Mensheviks). 1917 Presidium member, Petrograd Soviet.
Member, ed staff, Izvestiya Social Research i South Dakota. At 1st All-Russian Socialist-Revol Party and Social-Democratic Party Congress delivered a report on the war. Elected Presidium member, All-Russian Democratic Conference, where he defended the further coalition with Constitutional Democrats.
Presidium member, All-Russian Central Executive Committee. On its behalf opened 2nd All-Russian Congress of Soviets. After 1917 October Revol did not formally side with those who advocated armed struggle against Soviet regime.
1919-1920 worked as physician for Russian Soviet Federative Socialist Republic People's Commissariat of Health. 1920 deputy; Moscow Soviet. Russian Social-Democratic Workers’ Party Menshevik faction deleg to 7th and 8th Congresses of Soviets.
Early 1922 exiled from Russian Soviet Federative Socialist Republic as irreconcilable enemy of Soviet regime. 1923 helped organize United 2nd Socialist Workers’ International. One of Russian Social-Democratic Workers’ Party (Mensheviks) leaders abroad and ed of their central organ Sotsialisticheskiy vestnik.