Between 1959 and 1962, he worked as a teacher in Zürich. Different engagements as a teacher followed in (Göttingen), Japan and the US. From 1970 to 1999 Muschg was professor of German language and literature at theEidgenössische Technische Hochschule, Zürich.
He wrote the foreword toFritz Zorn's controversial memoirsMars. The book pointed out the supposedly "cancer-causing" lifestyle of Zurich's wealthy gold coast and provoked a scandal in Switzerland; its author died of cancer before its release. Muschg was also provocative with works likeWenn Auschwitz in der Schweiz liegt ("If Auschwitz were in Switzerland"). His detractors[who?] suggest that Muschg was writing without direct experience. A theme of his newer works is often love in old age.
Baiyun oder die Freundschaftsgesellschaft; Läufer und Brücken – eine unveröffentlichte Erzählung. Ausschnitte aus der Lesung in Hoser's Buchhandlung am 4. Oktober 1979 (Hoser's Buchhandlung, Stuttgart, ohne Nummer) (1 LP)ISBN3-921414-05-9