Therese Keller began her career as a professional puppeteer in 1949 and, after opening her own theater in 1950, quickly became successful throughout Switzerland and abroad. By the end of the 1960s, she was arguably the most famous puppeteer in her country. Periods of personal crisis led her to become involved in social action, in the children's village run by the Swiss Worker's Aid Society in Rimini in 1956, and in 1964-1965 in a Christian Peace Service project on the island of Lefkada in Greece. During these periods abroad, she continued to put on plays for puppets in the language of the country. She died in 1972 at the age of 49, having written nearly eighty plays.