Major musical anniversaries seem to be somewhat thin on the ground this year. However, the London Sinfonietta has certainly found a deserved case to commemorate when, from 3pm today in London's Queen Elizabeth Hall, the ensemble explores the life and work of Hanns Eisler (1898-1962).

Throughout his career, Eisler was a controversial figure: as a devoted communist, the early successes he achieved in Germany were brought to a sudden end by the Nazis. Though born in Berlin, by the turn of the last century, Eisler's family had already moved to Vienna. The self-taught Eisler initially studied music from books and scores; and it was only after the First World War that he eventually became a pupil of Schoenberg.

Eisler's own fledgling chamber compositions from the early 1920s are clearly influenced by the Second Viennese School. Yet, interestingly, at the same time that his burgeoning musical language was becoming more complex, Eisler's political views had clearly gravitated towards Marxism.

In 1926, he joined the German Communist Party and his subsequent distaste for the direction new music was taking eventually led to a bitter break with his mentor, Schoenberg.

For a man whose initial mature compositions had proved so chromatically dense in harmonic incident, Eisler now made a sudden turnaround and began penning boisterous, highly melodic marching songs.

The year 1930 evinced the formation of a very different artistic partnership to Eisler's flirtation with the Second Viennese school - a bond with his exact contemporary and spiritual equal, Bertolt Brecht.

When Hitler came to power in 1933, the activities of all those involved in the German workers' movement came to a halt. For Eisler, there followed 15 years of exile and 15 years of music almost solely devoted to the overthrow of fascism.

Initially, Eisler worked again with Brecht in Denmark, but then headed for Paris, Spain, Mexico and, eventually, Hollywood. Schoenberg, too, was in California but it was to Brecht that Eisler again turned, providing music for the playwright's Galileo.

In 1947, Eisler, Brecht and others, already exiled from their homeland, became outsiders in their new country; they were brought before the notorious Committee of Un-American Activities, accused of communist subversion.

A worldwide protest on Eisler's behalf was organised and he was eventually extradited to the new East Germany. Thus, for the last 12 years of his life, Eisler eventually got to work for the social system he had striven for for much of his life.

Yet, though he composed the East German national anthem, Eisler's relationship with the GDR became soured, as did his music and polemical tracts. By the time of his death he was sadly neglected and largely forgotten.

Yet in his best works from the 1920s and 1930s, Eisler shows himself to have a unique and idiosyncratic musical voice, as in the pithy Small Symphony of 1932, given in tonight's concert. Here, four short movements in a relaxed and uncramped style form a left-wing meditation on neoclassical composition via a quirky standpoint which Eisler termed "the overthrow of convention".

Also on the line-up is the seminal Brecht collaboration, Die Mutter, and the overture and four songs to Nestroy's Viennese dialect comedy, Hollenangst.

Major Eisler exponent, H K Gruber (above) conducts this concert, which also includes the UK premiere of his own subversive, parodic and Eislerian composition, Zeitstimmung.

Queen Elizabeth Hall, SE1 (0171-960 4242) 3pm and 7.45pm today