“In one part” - this is the meaning of the title - was first performed in October 1968 in the faraway Havana in Cuba, most likely as part of some friendly co-operation between members of the Communist block. Be it as it may, it was played by the National Orchestra of Cuba conducted by M. Duchesne Cuzan during a festival of contemporary music and was later to be presented by the same orchestra at the “Warsaw Autumn”, but the musicians’ visit to Poland was cancelled. As a result, In una parte was premiered by Szczecin Philharmonic Orchestra under Renard Tchaikovsky on 11th October 1968. At the "Warsaw Autumn” it was heard as late as 1977, in the interpretation of Leningrad Philharmonic Symphony Orchestra conducted by Alexandr Dmitrev.
In una parte turned out to be Bacewicz’s last orchestral work and one of her last compositions, a kind of swan song. The composer once again demonstrated her preference for “pure music” free of extramusical references, which, in the context of Krzysztof Penderecki’s recent St Luke Passion and three years before Henryk Mikołaj Górecki’s Ad Matrem was quite a unique phenomenon. The more so, since Bacewicz in this work moved away from tradition (though without an ultimate break) and clearly embraced the avant-garde that had just been abandoned by its one-time prophets - Penderecki and Górecki. The avant-garde idiom is evident in In una parte in the lack of motif or theme development in the traditional sense. Motifs are not progressive in character and are not submitted to consistent development. Separate, brief musical thoughts are isolated from the others. Sound material is diffuse, the sound is rarified, “pointillistic”, with clusters. The highly varied sound colours endow the music with a kaleidoscopic quality. All this notwithstanding, the composer maintains a creative discipline and emotional moderation - a style which she had been developing for some time, and which reached its apogee in In una parte. At a time of return to tradition, especially - to Romantic emotionality, the time of a radical shift in composers’ attitudes to musical time and a generally marked trend towards the use of extramusical inspirations, Bacewicz’s solitary stance could hardly have met with enthusiasm, but it certainly proved her independence and creative consistency. It is due to these qualities that Grażyna Bacewicz has her own place not only in music history, but also in concert programmes.