Born in 1937 in Miliunai near Vilkomierz in Lithuania, he studied at the Music Department of the Teacher Training Institute in Vilnius (1957-61) and subsequently, in 1964-69, at the Conservatory in Kiev (composition with Boris Lyatoshynsky). Since 1972 he has lived in Vilnius. He is Head of the Composition Department in the city's Music Academy. As a member of the Council of the Sajudis movement (1988-1992), he was involved in politics for the cause of the country's independence. In 1992-94 he served as Lithuania's first ambassador to France, Spain and Portugal (with the embassy's seat in Paris). He is a recipient of the Lithuanian State Prize (1996). His works have been performed at numerous international festivals.
Osvaldas Balakauskas has created his own, highly individual and precise musical system, which is characterised by the discipline of pitch and time relationships, controlled expression and structural logic. He outlined the harmonic aspect of the system in his book Dodekatonika whose first volume was published by the Music Academy in Cracow. His output comprises a diversity of genres and approaches, from quasi-Baroque to neo-impressionistic and postmodernist.

Selected works: String Quartet No. 2 (1971), Chamber Symphony 'Les Musiques' for cello and wind quintet (1972), Ludus Modorum, concerto for cello and chamber ensemble (1972), Studi sonori for two pianos (1972), Symphony No. 1 (1973), Mountain Sonata for piano and symphony orchestra (1975), Like a Touch of a Sea Wave, three pieces for violin and piano (1975), Orgy. Catharsis for electric cello and tape (1979), Symphony No. 2 (1979), Passio strumentale for string quartet and symphony orchestra (1980), Concerto for Oboe, Harpsichord and String Orchestra (1981), Chamber Symphony 'Tracery' for flute, violin, cello, piano and tape (1981), Sinfonia concertante No. 2 for violin, piano and symphony orchestra (1982), Do Nata for viola and cello (1982), Dada Concerto for soprano, tenor, two basses and instrumental ensemble to a text by Leonardas Gatauskas (1982), Spengla Ula for string orchestra (1984), Bachjahr for flute and chamber orchestra (1985), Tyla - Le silence for four voices and chamber orchestra (1986), Once More for two pianos (1987), Opera strumentale for orchestra (1987), Macbeth, ballet to a libretto by Smoriginas (1988), Ostrobothnian Symphony for 20 stringed instruments (1989), Veda - Seka - Budi for five percussionists (1990), Chopin-Hauer to a text by Schopenhauer for soprano, tenor, two pianos, viola, actors and tape (1990), Rain for Cracow for violin and piano (1991), Polilogas for alto saxophone and 20 stringed instruments (1992), Meridionale (Hommage ˆ Witold Lutos¸awski) for chamber orchestra (1994), Retrospective II for cello and piano (1994), Maggiore-minore for viola, saxophone and piano (1994), Solěa - Gala for cello or double-bass and two pianos or tape (1995), Bop-Art for trombone and piano (1995), Requiem for mezzo-soprano, chamber choir and string orchestra (1995), Betsafta for cello, piano and string quartet (1995), Erasmus for trumpet, trombone and tape (1996), Concerto rk for violin and chamber orchestra (1997), String Quartet No. 3 (1998), Symphony No. 4 (1998), Tristan for guitar, flute and piano (1998), Con brio for violin and chamber orchestra (2000), Dal vento for cello and piano (2000), Symphony No. 5 (2001), Rex Re for flute, violin, viola and piano (2001), La lointaine, chamber opera to verse by Oscar Milosz for three singers, nine instruments and tape (2002), Seasons for two pianos (2002).