The article sets out to prove the hypothesis that the sonoristic aspect of Serocki's music is one of the main indicators of his mature and late style. The tendency to compose polychromatic sound structures is already marked in the works dating from the 1950s, and continues until the final years of his creative development. The composer combines sonoristic and dodecaphonic techniques with aleatoric methods of shaping the work, as well as - in a few compositions - with elements of traditional techniques.