He worked as a senior editor and cultural critic for the Süddeutsche Zeitung from 1959, contributing reviews and articles on music, literature, and theatre.
In 1958, he was awarded a doctorate in German Studies at the University of Tübingen on the subject of Franz Grillparzer's dramatic style.
Although Kaiser was known for his discussion of famous pianists (like Arthur Rubinstein, Vladimir Horowitz, Glenn Gould, Sviatoslav Richter and Friedrich Gulda), he spent a large portion of his time presenting young interpreters in the art of piano playing.
[5] In 2009, he donated his extensive private archive to the Deutsches Literaturarchiv Marbach as a Nachlass (literary estate).
Besides letters from Theodor W. Adorno and Alfred Andersch, this archive contained correspondence with Ingeborg Bachmann, Ernst Bloch and Heinrich Böll.
With 170,000 listeners, Kaiser's lectures are considered as some of the most successful to date of the Münchner Volkshochschule [de].