He was a teacher in a camp for children in Bad Aibling run by the International Refugee Organization, where his students were orphans who had been persecuted for racial and political reasons.

[4] In the late 1950s, he became one of the first journalists of the American broadcaster Radio Free Europe,[3] running a daily literature feature in Czech, which contained poetry and music.

He was vice-chair and later chairman of the Modern Language Association (MLA), and he served on the jury of the Ingeborg Bachmann Prize for ten years.

[2]: 22 From 1974, Demetz wrote as a literary critic for the Frankfurter Allgemeine Zeitung,[4] invited by Marcel Reich-Ranicki,[5] and also for Die Zeit.

[4] In 1997, he published a key work, Prague in Black and Gold: Scenes from the Life of a European City, both a history and personal memoir, reflecting the city that inspired Johannes Kepler, Rabbi Judah Loew, composers Mozart, Antonín Dvořák and Bedřich Smetana, and authors Rilke and Kafka.

[6] He wrote autobiographic books, including a collection of essays, Böhmische Sonne, mährischer Mond in 1996, and Mein Prag in 2007, narrating his experiences under the Nazi occupation.