Osmo Vänskä started his musical career as an orchestral clarinetist with the Turku Philharmonic (1971–76). He then became the principal clarinet of the Helsinki Philharmonic from 1977 to 1982. During this time, he started to study conducting with Jorma Panula at the Sibelius Academy, where his classmates included Esa-Pekka Salonen and Jukka-Pekka Saraste. In 1982, he won the Besançon Young Conductor’s Competition.

Vänskä became principal guest conductor of the Lahti Symphony Orchestra in 1985, and chief conductor in 1988. He concluded his tenure with the Lahti Symphony Orchestra in 2008 and is now the orchestra’s Conductor Laureate. His complete set of Sibelius symphonies with the Lahti Symphony Orchestra, also on the BIS label, has garnered widespread acclaim. He has recorded extensively with his Lahti orchestra for the BIS label, including music of Kalevi Aho, Einojuhani Rautavaara, Bernhard Crusell, Uuno Klami, Tauno Marttinen, Robert Kajanus, Sofia Gubaidulina, Joonas Kokkonen, Jan Sandström, Jean Sibelius, and Fredrik Pacius.

Vänskä was chief conductor of the Iceland Symphony Orchestra from 1993–1996. In 1996, he was appointed chief conductor of the BBC Scottish Symphony Orchestra (BBCSSO), and served in that capacity until 2002. With the BBCSSO, he made recordings of the complete Carl Nielsen symphonies for the BIS label.

In 2003, he became the music director of the Minnesota Orchestra. Vänskä and the orchestra have received critical praise, and he is generally regarded as having enhanced the quality of the orchestra.

In May 2008, an orchestral piece composed by Vänskä titled “The Bridge” was premiered by the Metropolitan Symphony Orchestra, led by William Schrickel, assistant-principal bassist of the Minnesota Orchestra. In January 2014 Vänskä and the Minnesota Orchestra won a Grammy for best orchestral performance for the album of Sibelius’ Symphonies Nos. 1 and 4.