The musicians of the Ensemble Phorminx present central stations in Helmut Lachenmann’s oeuvre: from "Pression" for solo cello of 1969 or the clarinet piece "Dal niente", "Toccatina" for violin, or "temA" for flute, voice and cello to the trio "Allegro sostenuto" of 1986–88. These stations can be categorized by central questions and problems of composition, but they just as emphatically document a constantly progressing development that never comes to a standstill, much less settles down into a “style.” If in works like "Pression" or "Dal niente" Lachenmann worked out his idea of a “musique concrete instrumentale”, in works like "Allegro sostenuto" he permitted a series of approaches to design and procedure that he had categorically excluded from his early works.