From 1912 until 1959, Zulliger was a primary school teacher in Ittigen, Switzerland. He is remembered for his pioneer work of applying psychoanalytical practices into the
education of school children, mostly from rural, working-class and under-privileged environments. He was introduced to modern
psychiatric thought by educator Ernst Schneider (1878-1957) of the ''
Bern-
Hofwil Teachers' Academy''. Zulliger enthusiastically studied the works of
Sigmund Freud and
Alfred Adler, subsequently becoming an analysand to Swiss
theologian and lay psychoanalyst
Oskar Pfister. Later on, Freud became interested in Zulliger's work, and visited him twice in Switzerland. Zulliger had an intuitive understanding of children, as individuals, and also when they engaged in interactive group environments. He conducted research of children in regards to their difficulties at school, the games they played, and numerous other aspects of childhood. He published many articles on his personal reflections and observations of school children in the journal
Zeitschrift für psychoanalytische Pädagogik ("Journal for psychoanalytic paedagogics"), of which he became a co-editor in 1932. In the years 1930 to 1935 he developed his
Spieltherapie (
Play therapy), which he designed to be
deutungsfrei, free from interpretation. His understanding of the character and function of
child's play and of the psychotherapy resulting from this were later lead down in his widely read book
Heilende Kräfte im kindlichen Spiel (literally: ''Healing forces in children's play
/ vide Works'' section below). After
World War II, Zulliger's work contributed to the re-kindling of psychoanalytic instruction in Europe. Zulliger is credited with development of the "Tafeln-Z-Test", which is a modification of the better-known
Rorschach test. In addition to his books on child psychology, he was also a prolific author of books of
juvenile fiction. Both types of books have been translated and published in altogether 13 foreign languages (apart from German), including English, Spanish, French and Italian. ==Play Therapy==