Zbynek Vostrak studied composition privately with Rudolf Karel (from 1938 to 1945) and simultaneously was a student of conducting with Pavel Dedecek at the Prague Conservatoire from 1939 to 1943. During these years he was a member of the Prague Radio Orchestra and from 1945 until 1948 taught at the Prague Conservatoire. Beween 1946 and 1947 he held two further positions, one as a teacher at the Academy of Music and Performing Arts in Prague, the other as conductor of the Orchestral Association in the capital. From 1959 to 1960 he was conductor of the opera company in Ustí nad Labem while, in later years, he was a guest conductor in both Prague Radio and the National Theatre. Later on, he was also an artistic director of the modern music ensemble, Musica Viva Pragensis (from 1963) until the ensemble was officially abolished in 1973.
Up to the year 1963 Vostrak developed in the tradition of Czech romantic music. Beginning with his cycle of songs entitled While Falling Asleep, he turned to dodecaphony and techniques proceeding from this particular compositional principle. In the following years Vostrak employed the means of expression characteristic of the style known by the general title of New Music.
Starting with his septet "Affects", op.32, composed in 1963, the composer used aleatoric techniques and the graphic notation associated with these. During the late 1960s and early 1970s he was widely engaged in composing electronic music which he sometimes combined with live performers.
Zbynek Vostrak' s great talent found its expression in the first stage of his career as a composer, during which he wrote several succesful operas and ballets.
The following phase featured almost exclusively concertante compositions with a predominance of instrumental music. Vostrak' s works were and stil are regarded as pioneering achievements in this field and were duly acclaimed as such. As a resuft of Czechoslovakia' s official cultural policy in the 1970s and 1980s, particularly in relation to the kind of music composed by Vostrak at that time, the composer had steadily decreasing possibilities for performing his compositions at home, even though he had - in some cases - succumbed to official pressure by resorting to the use of cover-up titles for some of his works. The revival of Vostrak' s innovative compositional style was connected with programmes prepared by an association of young musicians called Agon (founded in 1983), which has since carried on the tradition, launched by the Musica Viva Pragensis ensemble.